High quality slim style Chrome Vanadium steel spanners. Hardened, tempered with a mirror polished finish for corrosion resistance. 144-Tooth WallDrive® ratchet ring giving ultra-smooth action, requiring only 2.5° rotation to pick up the next tooth. Covers sizes 10 to 19mm. Open-end of the spanners have hex profiles with serrated jaws for extra grip. Supplied in storage/carry rack.