BigHead Bonding Fasteners Ltd. (Bournemouth, U.K.) has partnered with Caparo Vehicle Products (London, U.K.) to develop TwinDisk fasteners for composite sandwich panels. The female system features two 316 stainless steel disks, each affixed to opposite ends of an internally threaded stainless steel collar or threaded stud by means of BigHead weld technology. A hole is drilled through the sandwich panel top skin, core is removed, BigHead’s two-part FS Acrylic adhesive is applied and the TwinDisk is pushed into the cavity. The bottom disk is bonded to the bottom skin while the the larger-diameter top disk adheres to the surface of the top skin, thus transferring tensile, shear, and lateral loads to both skins. Studs are supplied with adjustable top head, with fitting depths from 5 mm to 100+ mm (0.20 inches to 4.0+ inches). Threads are M4 to M16 (stud or collar).