Bought two grip safeties , this and the Ed Brown stainless for my STI. The Ed Brown fit very easily with minor fitting. Not so good with the STI, which you wouldn't think since it's for their gun. After trying to fit it, removing more and more material, I realized the the safety hole was drilled out of spec. The good folks at Dawson allowed me to return it for replacement. Hope that one works out. Just out of SEVEN BUCKS for returning it.