1A31GM is designed for outdoor year around use with fuel transfer pumps in the 3-30 GPM range. Calibrated for use with gasoline, diesel, or kerosene. This unit cannot be field calibrated. Uses AAA batteries that are good for 9000 hours. Accuracy is +/-2.5%. 1" FPT Aluminum housing. 300 PSI., +14 Deg. F. to 130 Deg. F . Measures gallons to 9999. B100 compatible (not for ethanol).

3A31GM is an industrial grade meter with 3-50 GPM range and can be field calibrated. Accuracy is +/-1-1/2%. Uses a lithium battery. Totalizer to 1MM gallons. This unit can be used for oils to 30 wt. 1" FPT Aluminum housing. 300 PSI., +14 Deg. F. to 130 Deg. F.

3A32GM is same as above, but in 2" FPT ports for 30-300 GPM.