A pluggable LC adaptor comprises a LC adaptor housing and an assembly, wherein the assembly is disposed in the LC adaptor housing. The assembly comprises: a first fiber collimator having a first lens; a first LC ferrule; a first fiber, where the first fiber is partially disposed inside the first LC ferrule and partially disposed inside the first fiber collimator; a second fiber collimator having a second lens; a second LC ferrule; a second fiber, where the second fiber is partially disposed inside the second LC ferrule and partially disposed inside the second fiber collimator; and an optical passive element disposed between the first collimator and the second collimator. The optical passive element may be a thin film filter or an isolator core.