These jumbo hex keys are made from tough, heat treated steel and have a black oxide finish for greater durability and corrosion resistance. Supplied with a handy storage case, the set includes large sizes 8mm, 10mm, 12mm, 14mm, 17mm and 19mm. They are made from heat treated steel with a black oxide finish and come branded by Am-Tech. This set contains sizes: 8, 10, 12, 13, 14, 17 & 19mm. It is an ideal gift.