The Model 464 Electronic Pump Control Unit is available in 125 psi or 250 psi versions and uses 4 AA alkaline batteries that last up to 100 hours of normal use. These controllers can also be operated manually if your batteries run out in the field, using only a compressed gas source. The pump control unit has automatic pre-set sample modes from low through high flow settings. In addition, up to 99 user-created flow rates can be saved in FRAM memory. The unit allows faster purge rates and precise low flow control to ensure a representative sample at 100 ml/min or less when sampling for VOCs (Volatile Organic Compounds). These convenient pump control units are rugged, dependable and suitable for all environments. Quick-connect fittings allow instant attachment to dedicated well caps, portable reel units and to an air compressor or compressed gas source.