[5 of 5 Stars!]Trigger scale is easy to use and very accurate. Make sure pistol is unloaded before doing any work or test trigger pull. Also make sure to have same placement on trigger everytime and pulling the same way. If need be use white out on trigger and scale lever (white out comes right off). If You own a glock then this is a must have. Glocks list most all there pistols at 5.5 lb pull. Sad to say there way way way off.....Before doing any work on any pistol or rifle use this scale to see where factory trigger is first, then start doing the work. Do only 1 step at a time to see if Your making it worse or better. Take 5 readings if need be and write them down with what You did, then move on to whatever else You will do to the firearm... 1 upgrade , 5 triigger pull readings, next up grade , 5 trigger pull readings, ect ect ect. Do this tell final completion and almost broke ,) God bless ,work safe and take Your time.