Bondhus 12210 - Hex Tip Hex Key L-wrench w/ProGuard Finish. Bondhus' ProGuard Finish is a special corrosion resistant finish that uses Bondhus' special dry surface technology. Bondhus' ProGuard Finish is environmentally safe, provides better tool grip and is 5 times more corrosion resistant. Short Arm. Size: 3/16 Length: 2.8.All Bondhus Tools are made with Protanium High Torque Steel, which is up to 20% stronger with more torque and twice the wear resistance of standard steel grades.