Thomson Dropper Seatpost Clamp Nut, Bolt and Washer Your Thomson seatpost is built to take abuse but its fragile hardware is not. This Nut/Bolt/Washer assembly is the perfect way to replace your stripped, corroded or mud incrusted hardware and keep your post going strong. For use with Elite and Masterpiece seatpost models. The Nut/Bolt/Washer set includes one bolt, one washer and one nut. Two sets are used per seatpost.