Monitors ensure dry conditions are present downstream of compressed air dryers. They show a blue to pink color change from 20% RH through 80% RH. Wall-mounted electronic humidity alarms come in 1 /8 to 1 /2 in. NPT connections for operating pressures to 2000 psig. Operating pressure is 150 psig with sample flows of 0.1 scfm.

Twin Tower Engineering Inc., (800) 700-8537, www.airdryers.com