Liquid contacts only tubing. Outputs to 2.3 GPD. Available in standard, deluxe or external output control models. All pumps feature 3/8" tube nut connections. 115 V/60Hz standard motors. Solid state output adjustment in one-minute, or five second intervals. Self priming, even against line pressure. De-gassing valve design eliminates gas or air accumulation in head. Precise output control by means of a digital touch pad wit LED readout (Deluxe models) or, percentage controller (Standard models). Weather proof, NEMA 3R. Advanced cooling, efficient, longer lasting. Silent alarm warns of pump tube failure. 200:1 output rate adjustment (on Deluxe models). All ball bearing motor for smooth, powerful operation.