Made from Chrome Vanadium Steel to withstand high fatigue and wear High tensile strength and structural rigidity for a longer lasting tool Heat treated for improved corrosion and abrasion resistance Polished finish for a premium look and feel Material Cr-V Steel Type Ring Spanners 1pc 6x7mm Ring spanner 1pc 8x9mm Ring spanner 1pc 10x11mm Ring spanner 1pc 12x13mm Ring spanner 1pc 14x15mm Ring spanner 1pc 16x17mm Ring spanner 1pc 18x19mm Ring spanner 1pc 20x22mm Ring spanner 1pc 21x23mm Ring spanner 1pc 24x27mm Ring spanner 1pc 25x28mm Ring spanner 1pc 30x32mm Ring spanner 1pc Double layer tetron pouch