Glass Mosquito Feeder, Large, 50mm Dia. Feed Area, Membrane Style. Glass mosquito feeder, Similar to CG-1835, but with a larger feeding surface. Mosquito feeding area is 50mm diameter. The outer chamber is for circulating 37C water and an inner chamber into which the blood is injected. Parafilm is stretched over the lower portion of the inner chamber. The assembled feeder is held on top of the screened box. Feeder has 10mm O.D. hose connections, while the blood chamber has an O.D. of 56mm where the Parafilm is installed.