Nonsparking adjustable wrenches won’t spark during use and are suitable for use in flammable environments. - They have a screw mechanism located at the bottom of the head that adjusts the jaws for a tight grip on a variety of fastener sizes. - These wrenches contain no iron, are nonmagnetic, and are suitable for use with magnetic resonance imaging (MRI) equipment. Material / Aluminum Bronze Finish / Natural Overall Length / 12 in Jaw Capacity / 1 1/2 in Grip Style / Plain Adjustment Type / Groove Nonsparking / Yes Non-Magnetic / Yes Corrosion Resistant / Yes End Style / Hang Hole Head Type / Standard Jaw Material / Nickel Aluminum Bronze Measurement Type / Metric, SAE Opening Type / Adjustable Weight / 1.3 lb Standards / ASTM F2503, ASTM A342, FM Approved Tether Style / Tether Ready