ARB CKMP12 Air Locker Accessories

• ARB On-Board High Performance 12 Volt Air Compressor

I've had a number of compressors over the years. Some have been portable, others have been hard-mounted to my vehicle. I've been looking to replace the QuickAir system I've had for 10+ years and settled on this ARB unit after hearing good things about their compressors from various 4x4 shops.

You get exactly what you see in the picture, plus a manual and a velcro strap for the air hose. My air hose measures a full 20' and the battery cables measure seven feet. You don't get a full 27' of reach since the battery cables have to reach up into the engine bay, but it still has an impressive reach. The coiled air hose on my old system makes it easy to store away, but since it never fully unravels the user can't reach the maximum distance. The ARB hose unravels nicely and allows the user to reach a full 20' away from the compressor. With the hose tightly coiled back up, everything fits well inside the case when you're done. There is even a bit of room left over for an air pressure gauge or other widget.

Probably the best feature is the pressure switch on the unit that shuts it off at a certain PSI. My old compressor just keeps running and sending air down the hose. Since the ARB tire attachment is sealed when not inflating, the pressure builds up in the hose and the compressor shuts off. That way the motor isn't running when you're not inflating something. A great feature since this is not a 100% duty cycle compressor.

I had a hard time getting the tire inflator attachment to fully grip the stem on one of my truck's tires. I've had that problem in the past so I think it is an issue with the stem, not the attachment. Still, I lost a few PSI before getting everything "happy". Since a compressor's performance decreases as the pressure increases, I timed it inflating my 275/70R18 (basically a 33x10.5") tire from 68 to 78 psi. The compressor took about 90 seconds to add the 10 psi. It definitely isn't a high-volume compressor, but that's better than the past few compressors I've owned.

If you're looking for something to air-up your tires after a long day of offroading, I'm willing to bet this compressor will take too much time. But if you want something to keep your vehicle and trailer tires at the correct PSI, then this is a great little unit.