The GC-Series pump utilizes the balanced 3-gear set unique to Smith pumps. The internal porting and superior constructionenables these pumps to handle continuous duty service applications and pump against high differential pressure. The GCSeries features a permanently set internal bypass valve at 90 psid. The L series option is included to increase pump capacity 25% higher than the capacities quoted for the GC-1 in the table below. Superseal is included to greatly increase productive seal life. Utilizing a hermoplastic seal ring that continually seats itself even in conditions of high vapour concentrations; the seal ring actually rotates at one-half shaft speed. It is sealed for life and does not require periodic greasing.