Abstract: Disclosed is a connector assembly tool that performs three assembly functions on FC and ST type connectors having a factory installed fiber in response to moving a handle from a first to a second position, namely activating an optical fiber alignment device (a slider) to align an optical fiber of a given cable with a factory installed fiber in a connector and securing such alignment in place by crimping a crimp tube disposed about the cable sought to be connectorized while maintaining an abutment between the factory installed fiber of the connector and the optical fiber sought to be connected to the connector, such tool comprising a base, a car slideably disposed on the base moveable from a first to a second position, a handle pivotably mounted on the base slideably engageable with the car and moveable from a first to a second position, a stop device on the base engageable with the handle when the car is in the second position and a fiber holder affixed to the base and spaced apart from the car and stop devic