In accordance with an embodiment, a transmitter optical subassembly (TOSA) module is disclosed with a base portion that provides one or more mounting surfaces to mount a laser diode and associated driver circuitry in close proximity to allow for direct coupling without the use of an intermediate interconnect device, such as a flexible printed circuit or other interconnect device. The TOSA module base further includes a cylindrical shaped portion with a passageway extending therethrough. The substantially cylindrical shaped portion allows the TOSA module base to mount to a multi-channel TOSA housing via a Z-ring or other suitable welding ring without the use of an intermediate device such as a welding cap.