ARO R37121-600-VS 1/4" NPT Air Regulator with Gauge

This may well be the best regulator I've seen. If I have one complaint, it's that the gauge seems small. That's no surprise, though. It's integrated into the regulator, and the whole block is rather small. Even so, it's a small complaint. Everything is well-marked and legible, and I am most impressed with everything else about it.I use a 30-gallon, oil-lubricated automotive compressor to run an airbrush. This is probably overkill, but for 5 minutes of noise, I get 2-3 hours of quiet work time. Unfortunately, my compressor has been eating regulators at the rate of one a year, though the last one only lasted 2 months. They work fine at 40 lbs, and may even work well at higher pressures. But sooner or later, when I run the pressure up to 80 or 90 lbs to fill a tire, the thing fails. As you may know, a regulator usually costs $20 to $60. It's a bother.The regulators I've bought at the Big Box stores seem really cheap. Their performance has been lackluster with several pounds of pressure loss when I actually start spraying. I've had replacement regulators fail right out of the package, too. Not good! With respect to most of the actual failures, I've since learned that it is extremely important to raise and lower the pressure slowly - more slowly than I've been doing it. Raising and lowering the pressure too quickly puts undue stress on the springs and seals. But the pressure and quality issues are still a bother, and I still needed a new regulator. So, I chose this one because I-R is a respected brand, this looked well-made, and the price was right.I'm happy to report that this is an outstanding piece of hardware, and apparently bargain priced. Other sites want $40 to $50 for the same unit. First, this has a very handsome, modular design. Second, all the parts seem well-made and fit together nicely. To adjust the inner range band, you do need to carefully remove the front housing, It snaps off and reveals the gauge assembly. Then, you move the yellow arrows as desired to set your pressure range. You pop the housing back into place and all is good. If you want the pressure knob on top, you remove the housing, remove a couple screws, carefully turn the gauge assembly 180 degrees, replace the screws, and replace the housing. Done!Once installed, I found the regulator has very little pressure drift - maybe a pound or two. Very Happy! Visiting the I-R site, I found that the company recommends putting a dirt & water filter between the air source and the regulator. No stock consumer compressor I've seen has this, and I've noticed buildup of contaminants in a couple of my worn regulators. So, this seems prudent and I will soon install a good filter unit to better protect my regulator.I recommend this as a very good, bargain-priced replacement regulator. I expect this to perform better and last longer than any other regulator I've tried. I will try to post updates over time. Thanks for reading.

I like this because of:1. Performance. In particular ability to deliver volume with less pressure drop than the 4 other regulators I tested. With the tank pressure set at 100PSI, I observed the output pressure drop as it delivered air to an air blower with the regulator set at 80 and then 60. The pressure drop with this relatively high flow was between 1/3 and 1/2 that of four other regulators I had available. One on a Porter Cable compressor, one on a Rolair compressor, a cheapo Harbor Freight unit, and another one I had lying around of unknown origin. I couldn't find published curves for this regulator (or any other small regulator for that matter), but it seems much better than the others I have.2. Configurability. It's a handy feature to be able to configure it any way round. The gauge comes off and can be attached on either side, either way up, so left to right flow, or right to left flow with the knob top or bottom are all possible.3. Build quality. Seems good.

I needed a regulator for my compressor as the old one was damaged.I quick review found this regulator with decent ratings.So, it works fine.Some issues you should be aware of-1- It has a very small pressure gauge included. It works fine but, is difficult to read.I bought an external larger faced gauge that I can read more easily.2- The air in and out ports were in the opposite direction from what I needed. Some reviews said it is easy to reverse, I did not try-Instead I installed it upside down. It works fine.3- It is fine for my home shop but, for heavy commercial use I would not recommend this regulator.Go for a high volume regulator- maybe with an air dryer / water separator inline.So, I recommend this for home use and light industrial use.

The regulator on my air compressor was leaking, so I replaced it with this ARO unit. I use my air compressor to keep tires inflated, and for pneumatic tools (impact wrench, cutter, and grinder).Pros:1, It works pressure at the tools seems to be properly regulated.2. I can make fine adjustments to the pressure both up and down.Cons:1. The dial is a little on the small side, making it hard for my old eyes to read without getting my glasses.The original regulator was hard to operate. The pressure would vary after starting to use the tools. I had ignored this for the most part. After installing the ARO regulator, I've noticed better performance from the impact wrench in particular.I would definitely buy again.

High quality build and materials. Quality trusted brand. Feels very sturdy. Good size for a small semi-portable compressor. Combined with the matching water separator, it will make a great combination. Adjustment is smooth and the locking mechanism feels positive. My only complaint would be that the gauge is tiny. You'll need good eyesight, but I like how compact and protected it is, making it less vulnerable to damage if the compressor tips over in the truck bed.Follow Up After Installing: This is the best regulator I have ever owned on a compressor. Hands down. It is compact but very well made. The adjustment is smooth and easy to dial in to whatever pressure you want, from max pressure right down to 0 and all points in between. Very smooth and controlled, lets you be very precise. Maintains a consistent pressure wherever you set it. Fantastic! For the price and quality, it's a bargain.