PETOL "EL-MAC" SURGRIP VALVE WHEEL WRENCHES are made from aluminum-magnesium to minimize sparking and have a “fist-like” head to reduce slipping even on stubborn valves. The wrenches are designed for use in the petroleum, petrochemical, pulp/paper, mining, marine and power generating industries. Specifications: Overall Length (approx.): 9" Opening: 7/8" Weight: 13 ozs. Safe Practices And Procedures Valve Wheel Wrenches should fit over the valve wheel rim completely. Make sure that the wheel rim is in contact with the top of the wrench opening when applying force. Brace yourself firmly and pull rather than push when wrenching. (If necessary to push, do so with the flat of the hand rather than gripping around the wrench.) Keep the wrench in the plane of the valve wheel rim when pulling. Pulling at an angle increases the chance of slippage. Never apply excess leverage to a wrench by means of a "cheater bar." Never strike wrenches with hammers or other objects. Safety Goggles must always be worn by persons in any area where hand and powered tools are being used.