Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 52C1537-1 found under Ring Retract Sprock by Engineered Arresting Systems. The National Stock Number assigned to this part is 1710006898028, and the Federal Supply Class is . Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 52C1537-1.