In the box you get the inflator as well as a carrying bag and a bottle cage attachment so you can carry it on your bike. The unit is charged via a standard USB cable that's supplied. It’s noisy, dishing out 77dB in operation. And the pressure gauge can be difficult to read since, because it goes up to 250psi, that crucial 0 to 60psi zone is crammed into the first quarter of the dial. However, it pumped up our test tyre from 20 to 30psi in just under two-and-a-half minutes, with no fuss or faff. It’s a shame that the supplied accessories are so basic – just a ball inflator and two adaptors for inflatable toys – still, if you’re looking to spend as little as possible, then the Storm Force Mini does the job.

Size is probably the most important thing. The smallest inflators are around 20 x 20cm, so you can leave them in your car without losing too much luggage space. The best don’t skimp on the length of the power lead and air hose, which makes it easier to reach all four valves. Most can be preset to stop inflating when your tyre reaches the correct pressure. Smart storage case allows you to charge the inflator whilst still in the bag; with storage for cable The RTC4000, freed from the confines of cumbersome wires, allows the user to navigate around their vehicle with absolute ease. Its cordless design eliminates the issue of untangling wires or needing to adjust the unit to reach the other side of the vehicle. With the power and performance akin to a traditional Ring tyre inflator, the RTC4000 truly shines with its unhindered mobility. Compact and Practical Despite its smaller size, the Ring performed well, inflating the tyre faster than some of the larger models in this test. The Ring also retains a leisure inflator/deflator and is fitted with a Deflate button. We were also a fan of the foolproof knob and display set-up, and the smart carrying bag. Given most people are used to tyre inflators being the size of a kids lunchbox with wires and cables, this small handlheld design might come as a surprise. It's about the size of a standard 50cl bottle of water and not much different in weight either. To charge it up took about three hours when it first arrived and since then we've been charging it up between uses.Larger inflators include rechargeable batteries, which make them completely portable. These are a better option if you want to pump up, say, bicycle tyres, without having to wheel the bike next to your car. You may also need a larger inflator for tyres that need higher-than-average pressures, such as a larger van or campervan. What about extras?

The RTC4000 is not just an inflator but also a smart tyre pressure management system. The digital auto-stop feature ensures the inflator ceases once the set pressure is achieved, while the integrated memory function can store up to four tyre pressures in PSI, BAR or kPA. In case of overinflation, a deflator valve is incorporated for precise pressure adjustments. Adaptability and Convenience The RTC4000 has a digital autostop feature that will automatically stopinflating the tyre when the desired pressure is reached. The inbuilt memoryfunction allows you to store up to 4 tyre pressures in either PSI BAR orkPA. Should you have too much air in the tyre there is a deflator valve thatallows you to accurately achieve the pressure you require. The pressure is usually shown in two formats: bar and psi. There are typically two sets of these. The lowest is for normal use, but you may well see another set of higher pressures for when the car is heavily loaded, increasing the weight that’s pushing down on the tyres. As an extra bonus, for me at least, the expansion tank on our central heating needs to be charged to 3 bar (43.5psi), which is really awkward to do with my stirrup pump as you have to press it against the wall, making it hard to get the necessary force; with the Ring I can just plug it in and off it goes. When our plumber saw it, he went out and bought one straight away.Users will also appreciate the thoughtful design elements, including a potent built-in LED light to illuminate the wheel valve in poorly lit conditions, which can also serve as an emergency light. Furthermore, the RTC4000 comes in a smart storage case, which cleverly allows the inflator to charge while safely nestled inside. The inflator's compact size and lightweight design make it easy to transport, making it an excellent companion for motorcyclists and cyclists. Comes with a 3-piece adaptor kit for small inflatables such as sportsequipment and Presta bike valves.