On semiautomatic pistols, it attaches to the ammunition magazine. Some police departments, including Boston, have bought for off-duty officers. Boxes lockable either with padlocks or combination locks. Gun-makers Colt and Sturm Ruger ship guns in lockable boxes. Prices vary widely depending on whether the box is metal, plastic or other material.
Critics say boxes are too easy to break into.
Metal safes are sturdier but more expensive.