- Extend the life of your iSSi Thump pedals by replacing beat-up or missing pins with the Thump Replaceable Pin Kit. - Includes 36 steel pins and 2mm spacers to replace both sides of two pedals - The standard pin height out of the box is 3mm with a 2mm spacer. For more traction, remove the spacer under the pin head to increase pin height to 5mm.