thetford cassette toilet reed switch housing relay/fuse holder 
Thetford SC250 reed switch housing for C250 range of cassette toilets.
Thetford part number: 50716
The SC250 reed switch housing is used in the cassette toilet C250S, cassette toilet C250CS and the cassette toilet C250CWE it is listed as: 27. Reed switch housing and 28. Relay/fuse holder.