Forum RPM and SPM Tachometer Generators are available in explosion-proof and non-explosion-proof models. Each generator has an output of 10 VAC @ 1, 000 RPM in either direction clockwise or counterclockwise. 10 VAC @ 1, 000 RPM output.Explosion-proof model is listed by Underwriter's Laboratories (UL)for use in hazardous locations, Division 1, Group D (natural gas or the vapors from lacquer solvents, acetone, alcohols, and petroleum derivatives such as gasoline) and Class 2, Groups F and G.Easily mounted, with a direct connection to the pump pinion shaft by means of a flexible coupling or by a V-belt connection between the shaft and the generator pulley.A heavy-duty, oil-resistant electrical cord connects the generator to the RPM meter.Generator supplies all the power necessary for one or more Indicators no outside power or batteries are required. BenefitsCenter-point mounted drums ensure optimum accuracy.Smooth, machine-grooved drum surface extends cable life.Heavy-duty, high-grade structural steel construction with tapered roller anti-friction bearings and heat-treated alloy shaft provides a super strong anchor with exceptional durability.Proof-testing to 150% of rated capacity ensures superior reliability.Durable bronze wireline clamp inserts provide tight cable grip without damage to the line. Easy to install and service.