Lang Diesel Compression Tester tests cylinder pressure on diesel cars and trucks. The Lang Diesel Compression Tester features a handy deflator for releasing air and automatic resetting of gauge for repeat testing, and a swivel-end Quick Coupler for easy connection to all our adapters. The wire reinforced hydraulic hose is 16 1/2” long, and the 2 1/4” gauge has a dual scale dial with ranges from 0 – 1000 psi and 0 – 70 bar with easy to read red and black dial.