Style QC1. Used in conjunction with The 'Cooler Bleeder and the Series 2 Adapter. This inserts into the factory bleeding port found in many Chevrolet and Cadillac vehicles.  Used in place of General Motors / Kent Moore special tool GE-52079-10 and GE-47716-20.  See Connection Chart for exact fitments. 
 
Note:  Hand assembled in the USA, there may be cosmetic tooling marks on plug from assembly.