A pluggable module includes a pluggable body extending between a mating end and a cable end. The pluggable body includes a single-piece, unitary shell defining a cavity. The shell is seamless around a perimeter of the shell. An internal circuit board is held in the cavity and surrounded by the unitary shell. The internal circuit board is provided at an end of a cable communicatively coupled to the internal circuit board. The pluggable body is configured to be plugged into a receptacle assembly such that the internal circuit board is communicatively coupled to a communication connector of the receptacle assembly.