You might assume that dangerous power surges either come from lightning strikes or problems with equipment at the utility company. While these are certainly the most dramatic, and potentially damaging, around 50 percent of power spikes actually originate within the home.

Every time air conditioning goes on and off it creates an imbalance. The same is true of refrigerators, and other devices like washers and ovens. Normally these are small enough to pass unnoticed and don’t cause problems. However, if they cause a breaker to trip, or if there are wiring faults, the power surge could be strong enough to fry electronics and appliances. Surge protectors are the cost-effective solution to both types of hazard. Here's a list of the best surge protectors that fit a variety of different purposes.

— Best Overall: Belkin Power Strip Surge Protector — Best Budget: Tripp Lite 3 Outlet Portable Surge Protector — Best for Gaming PC: Plugable Surge Protector Power Strip — Best for Smart Home: Kasa Smart Plug Power Strip HS300, Surge Protector — Best for RV: Progressive Industries 30 Amp Portable RV Smart Surge Protector

We researched the product lines of numerous manufacturers in an effort to offer a comprehensive selection. Here are the factors that we considered when making our picks.

Performance: The level of surge protection, and the number of devices that can be protected are perhaps the most important features. In making our selections, we have  tried to showcase the variety available, and thus provide people with maximum choice.

User-friendliness: Surge protectors should be easy to understand, and fuss-free to use. We also looked at minor features like status indicators that might make a difference in terms of convenience.

Brand and Price: Buying from major brands like Belkin, GE, or Philips virtually guarantees you get high quality, dependable products. However, they frequently come with a premium price tag. While we avoided cheap, unbranded products, we did consider some of the better-known budget brands that offer value for money, and have proven popularity.

Why It Made The Cut: The low-profile Belkin surge protector is both physically robust, and provides a high level of protection. The 12 outlets make it ideal for home or office use and the best surge protector overall.

Specs: — Joules: 3,490 — Outlets: 12 AC, 3 Landline, 2 Coaxial — Connected Equipment Cover: $200,000

Pros: — Clear protection status light — Can withstand 6,000 volts — 8-foott cord

Belkin is one of the leading surge protector brands, offering a range of equipment to suit different needs. This 12-outlet model has a low-profile design, and a useful 8-foot cord that should allow plenty of flexibility when positioning. Sliding safety covers keep small fingers from prying into unused outlets. There is also a useful cable tidy to help keep things neat.

Although it is wider than some, this surge protector allows good spacing between outlets. As a result it can accommodate numerous odd-sized plugs, such as those found on monitor transformers, some printers, faxes, etc. There is provision for RJ11 connectors typically found on landlines, and for coaxial connectors used with cable or satellite systems. However, this model does not have USB ports.

This surge protector’s energy rating is a maximum of 3,940 joules, which is sufficient for TVs, home theaters, office equipment, and PCs. The Belkin will protect against voltage spikes up to 6,000V, and has a clamping voltage of 500V. A small but clear LED advises of protection status. Plus, the Belkin surge protector is safety certified to the independent Underwriters Laboratory (UL) standard.

Why It Made The Cut: The Tripp Lite 3 is a convenient, inexpensive solution that has been designed to provide essential surge protection for personal devices both at home, and when traveling.

Specs: — Joules: 540 — Outlets: 3 AC, 2 USB — Connected Equipment Cover: $5,000

Pros: — Easy-to-carry in pocket or bag — Clear status indicator — Modest price

Cons: — AC outlet spacing is tight — Occasional faults with USB charging

The Tripp Lite 3 is a compact, low-cost device that plugs directly into the wall. Having no cable, it is particularly compact, and can provide essential surge protection both at home (on a bedside table for example), and when traveling. It offers three AC outlets and two 2.1A USB ports. Due to its small dimensions the AC outlets are quite close together. It can accommodate standard plugs, but transformers and other larger types may mean that only two are usable at the same time.

With a rating of 540 joules, the Tripp Light is mainly intended for low power personal devices such as MP3 players, tablets, and mobile phones. It will also offer some protection for laptops — any kind of surge protection is better than none at all — though 1,000 to 2,000 joules is generally recommended for full protection. An LED on the top of the Tripp Lite 3 gives a clear indication of its status, and the manufacturer says it will replace any unit that fails. This device also complies with the UL safety standard.

Why It Made The Cut: This is the best surge protector for gaming PCs because the Plugable surge protector has class-leading 4,320 joule rating for sensitive and high-value equipment like gaming PCs, further supported by particularly low clamping voltage.

Specs: — Joules: 4,320 — Outlets: 12 AC, 2 USB — Connected Equipment Cover: None

Pros: — Class-leading energy protection rating — Clamping voltage of just 330V — Built-in EMI/RFI filter

Cons: — Comparatively expensive — Slower USB charging than some

First impressions of the Plugable surge protector are of a device that is physically quite large. However, this does allow ample space to use all of the 12 AC outlets, where more compact models sometimes make this impractical. It comes with a choice of either a 6 foot- or 25-foot power cord, the latter being a safe alternative to using an extension cable. Long green status LEDs run down both sides so it’s easy to see whether the Plugable surge protector is working or not.

Energy protection rating is 4,320 joules, which is the highest we found. In addition, the clamping (pass-through) voltage is just 330V. Most competitors offer 500V, which many experts consider too high for laptops. The Plugable also includes filtering for electromagnetic interference (EMI) and radio frequency interference (RFI) which can be present in power or signal lines, and can disrupt sensitive audio equipment. There are 2 USB ports, though with 2.1A shared they don’t charge particularly quickly. The Plugable surge protector meets the UL standard for safety.

Why It Made The Cut: The Kasa smart surge protector from TP-Link offers six independently-controlled AC outlets, USB charging, and can work from WiFi or be integrated with various home hubs.

Specs: — Joules: 1,710 — Outlets: 6 AC, 3 USB — Connected Equipment Cover: None

Pros: — Control and monitor from any location — 6 independent outlets — Can operate from WiFi only

Cons: — Expensive — Additional purchase required for voice control

The Kasa smart power strip surge protector is a slender unit housing six independent AC outlets each with its own status light, plus three USB ports. With a rating of 1,710 joules, this surge protector is capable of protecting TVs, computers, office equipment, and home appliances.

The Kasa functions like any other surge protector if required, but its smart features extend control and flexibility. It can manage any of the connected devices independently from each other, via standard 2.4 GHz WiFi, and the free smartphone app. They can be turned on and off, or have timers or schedules set for them remotely. It is also possible to monitor energy consumption daily, weekly and monthly. There is integration for Amazon Alexa, Google Assistant or Microsoft Cortana, which offers the potential for voice command. The home hub needs to be purchased separately, and actual features may differ so this area requires further investigation. The Kasa smart surge protector has ETL safety certification.

Why It Made The Cut: Campground power supplies can vary in terms of both safety, and consistency. The Progressive Industries surge protector can indicate faults and prevent fluctuations damaging the devices inside your vehicle making it the best RV surge protector.

Specs: — Joules: 825 — Outlets: 1 — Connected Equipment Cover: None

Pros: — Testing and protecting in one — Tough, weather-resistant housing —  Integrated LEDs quickly identify faults

Cons: — Relatively expensive — May only survive single surge event

Plugging your RV into campground power can be a considerable risk. There is seldom any way to know how well the supply pedestal is maintained, whether it has been wired correctly, or the consistency of the power delivered. An unexpected surge running through the RV is potentially every bit as damaging as one in the home.

The Progressive Industries portable RV surge protector is a high-quality solution. It has clear LEDs to indicate faults with ground, open, and neutral wires, and will also warn of reversed polarity. If everything is clear, leaving it plugged in provides energy rating protection of up to 825 joules. The casing is built to withstand hard use, and has a tough, Lexan housing. It will operate in all weathers, with a temperature range from -40°C to +105°C (-40°F to +220°F). It is compact and easy to store when not required. Progressive Industries 30A portable RV surge protector is UL and CSA certified for safety. A 50A version is also available.

There are a number of leading brands in the surge protector market, including Anker, Belkin, GE (General Electric), and TP-Link. Panamax is known for high-end equipment. There are also popular budget solutions available from Amazon, Monoprice, and Monster, among others. Before buying a surge protector, it’s important to consider the following features:

The joule rating of a surge protector is often the headline figure, perhaps because numbers can be impressive. It’s an indication of the amount of energy the surge protector can accommodate before it fails. Higher numbers are better. Small devices like smartphones can be protected by around 500 joules. Most household appliances and PCs are safe with between 1,000 and 2,000 joules, though owners of large TVs and expensive gaming PCs might want to maximize protection with even higher rated models.

If a surge protector blocked voltage entirely, the equipment that was plugged in wouldn’t work. So in the event of an incident, some voltage has to be allowed through. This is known as the clamping voltage. Figures can be difficult to find. Many models throttle the surge down to 500 volts. The best surge protectors reduce this to 330 volts. It’s a bonus if the device has been independently certified as safe by CSA, ETL, or UL.

Each time a surge is absorbed, it weakens the surge protector. There is no way to know how long the device will last, as high energy surges do more damage than low ones. Eventually the surge protector could stop protecting your electronics. When this happens, some low-cost models simply fail, and allow the full current through. Better versions have an auto shut-off, which cuts off the electricity to anything plugged in until a new surge protector can be fitted. In either case a light may indicate that the surge protector has failed. Auto shut-off is the safer option in terms of protection, but it may not be appropriate if it’s important for the equipment plugged in to continue working.

Some surge protectors only provide standard household outlets. Others also include ports for USB, coaxial cable, and landline connections. The number and type of these will clearly have an impact on your choice. You might also want to check cord length, which can be anywhere from 4 to 25 feet. Bear in mind you should never plug surge protectors into an extension cord, or daisy-chain them together, as this will compromise functionality. It could lead to dangerous overheating, and the potential for a fire.

Some surge protector manufacturers offer a warranty that should cover connected equipment in the event of a failure. The amount provided for can be several hundred thousand dollars. However, it is very important to check the warranty terms, as claims can be challenging to prove.

If you need to protect devices worth thousands of dollars, then yes, the more expensive surge protectors are a worthwhile investment. However, the competitively priced solutions above will prove perfectly adequate in most cases.

Understanding the protection your devices need is key to choosing a good surge protector. The details provided in our ‘Things to Consider…’ section will help you make an assessment. When in doubt, go as big as your budget allows. There’s no such thing as too much protection.

It will depend on specification. Things like suppression level, number of outlets, and features like auto-shutoff all have an impact. Surge protector cost can be anywhere from under $20 to over $200.

Once again it’s a question of accurately assessing equipment demands. With compact portable models designed for phones and tablets, around 500 joules will usually be sufficient. High-performance models can provide over 4,000 joules of protection.

It’s important to understand the difference between the two devices. A power strip is simply a way to plug multiple devices into a single wall outlet. They do not offer any protection. A surge protector also allows extra devices to be plugged in, but it protects those devices from potentially damaging power spikes.

They are, particularly the latest smart appliances with WiFi capability, as these frequently contain more sensitive electronics than older models. In fact there is a whole range of appliance surge protectors specifically designed to combat potential problems.

Whether you have a few gadgets in your RV, or a home full of TVs, computers, and appliances worth thousands of dollars, it has to be worth protecting them from getting fried by inevitable power spikes. Fortunately, even the best surge protectors are very affordable. Our top pick, the Belkin , will suit many people’s household or office needs, and the Tripp Lite 3 is very convenient for those on the move.

This post was created by a non-news editorial team at Recurrent Media, Futurism’s owner. Futurism may receive a portion of sales on products linked within this post.