Reed switch for the Thetford C250 toilet models, with only a flush button and a single waste tank level indicator. This is a small circuit board incorporating the reed switch that senses the waste tank level. This is the basic version - described as the "one switch" model. This has one reed switch fitted (the red bar component) and a board part number of 50569. The board style may be one of two types. One type has the number on a small beige square near the contacts and the other style has the number by a small soldered-on component. Dimensions: 30mm x 40mm