Deez Bolts are flush mount chromoly crank bolts that are 3/8 inch x 24tpi, and are the stock bolts for the 1664 BMX Good Ol’ Cranks. Deez Bolts can also be used with many other crank spindles that use a 3/8 inch x 24tpi bolt (fairly common on 19mm 48 spline spindles) Cranks.