I bought three sets of these 4 lock packs from amazon for the price of one 8 lock safety 1st set. I installed them on three kitchen cabinet doors exactly as instructed (even had to go buy a 7mm drill bit) I tested them before and after on the first one which works 70% of the time and sadly the other two did not work and had to be pried open and left in unlocked position until I can find a solution or replacement. I believe the magnet is simply not strong enough to activate the release throuch the 1/4" of remaining door after drilling through as close as a can without puncturing the surface.