The topic notebook

Tyre Pumps and Inflators

How we research

A tyre inflator tops up your tyres to the pressure in your car’s handbook. Choose one by its power source, the pressure range it covers and its safety record. Our research on specific models is listed below.

Last updated: 19 October 2026

How to choose

  • Corded or cordless. A corded inflator plugs into the car’s 12 V socket. For example, a UK seller lists the AA AA5502 with a 3 m plug cord [1]. A cordless one runs from a rechargeable battery. Ring’s RTC4000 has two 2500 mAh batteries and also comes with a 3 m 12 V cable for when the battery is flat [2].
  • Check the pressure range covers your tyres. Makers state a range. The AA5502 is listed at up to 100 PSI [1], and Ring’s instructions give 0 to 120 PSI (0 to 8.3 bar) for the RTC4000 [3]. One bar is 14.5 PSI [4], so convert before you compare. Your own figure is in the handbook.
  • Look for a digital display and auto-stop. Ring says the RTC4000 stops inflating at the pressure you set and can store 4 pressures [2].
  • Check the noise rating. Ring rates the RTC4000 at 90 dB and advises hearing protection [3]. Not every maker publishes a figure, so it is worth checking.
  • Check how long it can run at a time. Makers give duty limits and cooling breaks. We did not find this for the models we have researched, so read the instructions in the box.

Checking your tyre pressure

The RAC says to park safely, switch off the engine and apply the handbrake. Find the correct pressure in the owner’s manual or on a sticker inside the driver’s door frame. Remove the valve cap, press a good gauge firmly onto the valve, and add air in small amounts, re-measuring each time. Check the spare as well [4].

The RAC says tyres count as cold after three to four hours without driving, so check before a journey. Use the figure for your load: fuller loads need the higher pressure listed for them. It advises checking once a month. Other advice varies, so before a long journey is sensible too [4].

GOV.UK says each tyre needs at least 1.6 mm of tread across the central three-quarters of the tread width and around the whole circumference. It also says that using a vehicle in a dangerous condition can bring a fine of up to £2,500, a driving ban and 3 penalty points [5].

Questions people ask

Should I buy a corded or a cordless inflator?

It depends on whether you want to deal with a cable and whether you will keep a battery charged.

The case for corded: there is no battery to keep charged, and it works when plugged in [1].

The case for cordless: no cable across the car, and it can be used away from the socket. It still has a cable for flat batteries [2].

Drawbacks: a corded unit depends on a working 12 V socket, and a cordless unit has a lithium battery that needs checking against recalls (see below).

Bottom line: corded suits a simple boot kit. Cordless suits people who value convenience and are happy to recharge.

Recalls and safety

Cordless inflators contain lithium batteries, so check recalls before you buy and if you already own one. Our product safety and recalls page explains how we check.

The Office for Product Safety and Standards published a recall on 23 July 2025 for Ring Automotive’s RTC6000 and RETC6000 cordless tyre inflators. A fault in the battery protection in certain batches can cause overcharging and a fire. The notice says to stop using an affected unit and points to Ring’s page for the batch codes [6]. We found no notice naming the RTC4000. Search the official recalls list for newer notices [7]. Recalls checked 19 October 2026.

Sources

  1. AA Digital Air Multi-functional Compressor [SAX-AA5502], The Safety Supply Company (UK seller listing), thesafetysupplycompany.co.uk. Checked 18 October 2026.
  2. RTC4000 Cordless Rechargeable Tyre Inflator, Ring Automotive, ringautomotive.com. Checked 18 October 2026.
  3. RTC4000 user instructions (PDF), Ring Automotive, ringautomotive.com. Checked 18 October 2026.
  4. How to check your tyre pressure safely, RAC, rac.co.uk. Checked 19 October 2026.
  5. Tow a trailer with a car: safety checks, GOV.UK, gov.uk. Checked 19 October 2026.
  6. Product Recall: Ring Automotive Cordless Tyre Inflator (2507-0008), Office for Product Safety and Standards, GOV.UK. Checked 19 October 2026.
  7. Product safety alerts, reports and recalls, Office for Product Safety and Standards, GOV.UK. Checked 19 October 2026.

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