These bolts may or may not contain locking serrations on the head. These bolts are commonly used when vibration in the final application is present. Over a generation some of these designs gained acceptance and approval from fastener consumers all around the world. From among the most proven, successful designs, Fasco offers standard and customer variations of these products: PT, Delta PT and Duro PT (originated by EJOT), Plastite, Remform (originated by Reminc), Hi-Lo DST dual spaced thread (originated by ITW Shakeproof).MATERIAL OPTIONS: Low Carbon Steel (Grade 2, Grade 4.6), Medium Carbon Steel (Grade 5, Grade 8.8), Alloy (Grade 8, Grade 10.9), Stainless Steel 302, 304 and 316.PLATING OPTIONS: Zinc (Trivalent), Various Color Chromates, Zinc Alloys (Zinc, Tin, Zinc Nickel, Etc), Phospate and Oil, Automotive Finish (Doerken, Magni, etc), Proprietary Finish (Dacromet, JS-500, Etc), and Passivation.