Isn't the 27 mag a 9 rounder? Mine is. The 26 holds 10.Mostly a G27, other times a G30. Either in a BH Serpa on my right hip. When I need to conceal, the G27 in a Galco Ankle Glove. Also, both Glocks have 10+1 in them, with a spare 13-round mag in a belt pouch.