Thank you for selecting Aerospace Aviation360 as your go-to distributor of part number 41-018 found under Guide Piston Med by Spectrum Associates Inc. The National Stock Number assigned to this part is 1615011899710, and the Federal Supply Class is 1615 Helicopter Rotor Blades Drive Mechanisms And Components. Our website is owned and operated by ASAP Semiconductor, a leading distributor of aviation and aerospace part numbers like 41-018.