TRYBE Defense Magazine Extension Base Pad Glock 19/23/26/27 9mm/.40 S&W 4/5-Round Red MAGEXTG194/5-RD-5RD. The TRYBE Defense +4/5 Magazine Extension Base Pad will add (5) 9mm rounds to any factory Glock 19 and (4) .40 S&W rounds to any factory Glock 23...