One 20" diameter vacuum fan handles up to 16 rows of corn or 32 rows of soybeans. Approximate hydraulic requirement is 13 GPM @ 2000 PSI. One SCV outlet and one low-pressure case drain connection are required to operate the system. The 3700 and 3800 models are equipped with two fans and a standard-equipment PTO pump system with oil reservoirs, coolers and filters. PTO Pump Packages are also available as options for other models. Cab-installed electronic gauges and planter-mounted analog gauges give you confidence vacuum levels are set correctly.