I already had an ARB deflator but decided to try it to see if it worked better and was pleasantly surprised. The brass fittings on the deflator are fairly stout and appear to be well made upon inspection. People who complain and say it takes too long probably haven't spent time with an ARB valve stem remover; I would say it takes at least twice as long. With them, you install them on your first wheel, walk around the car until you install them and deflate all four tires. Then you go back to the wheel you started with and check the tire pressure. If you started with a pressure of about 35psi, you will come back to about 25psi; Wait a few more minutes and check the pressure again. Valla, you're at 20 psi, bingo! Then, once you've installed the air dumpers, loosely go around the car and remove each one until they loosen and you've reached your target air pressure (+/- 2psi). If you're really picky you can check the pressure in each tire before you take it off, but I'd say it's a lot easier than squatting with each tire for 1-2 minutes and trying to do the same thing with the bleed do. core remover. For those who have complained that they don't deflate quickly enough, I've noticed that if you tighten them all the way, the airflow will be slightly restricted, but if you back them off about 1/4 turn, the air will be accurate published at this time. its top speed; So just play with them in your driveway to find that sweet spot. The way they worked was that two other buddies of mine gave up their ARB deflator and waited for me to finish to borrow their deflators; and for the price they can't be beat.