A fluid flow connector comprises a connector body which carries a first connector tube having a lumen for receiving a second connector tube when the connectors are joined. The first connector tube has a lumen and a lumen wall. The first connector tube typically has an end portion that carries a plurality of circumferentially spaced, outerwardly extending lugs to engage the second connector tube when connected. The fluid flow connector is made of a plastic having a flexural modulus that is low enough to allow deformation, permitting a connected, engaging second connector to pop loose from connection with the fluid flow connector when laterally struck, rather than breaking the fluid flow connector. Also, the first, fluid flow connector may optionally be frictionally retained in a retracted position where fluid flow is blocked through the connectors by a skirt of the second connector, which skirt has an inner diameter in frictional engagement with radially outer surfaces of the lugs of the first connector, for frictional retention of the connectors.