CHICIRIS Hex Socket Screws, Hex Socket Cap Cap Head Screw Set, 4-50mm Alloy Carbon Steel for Home and Office Appliance Communication Equipment(M3*50mm(Partially Threaded), 24pcs): Amazon.com: Industrial & Scientific
Amazon.com : 7artisans 50mm f1.1 Manual Lens for Leica M Mount M-M M240 M3 M6 M7 M8 M9p M10 - Black : Electronics
Amazon.com: M3 x 50mm Hex Socket Head Cap Screws,Pack 30-Piece,Stainless Steel,Full Thread,Metric,Knuled Head : Industrial & Scientific