Y50EX series circular connectors are made conforming to the standard GJB598A, in the light of the U.S.MIL-C-26482. The series is compatible with JY series, MS series and YB series. The same type of response plugs and receptacles can be interchanged. The series connectors with bayonet coupling mechanism have the features of small volume, light weight, high density, convenient application, high durability of pluging and unpluging, etc.