The Unbrako alloy steel shoulder screw has a black oxide finish, knurled socket cap head, and hex socket drive, and meets American Society of Mechanical Engineers ASME B18.3 specifications. Alloy steel is often used in applications where strength is the primary consideration, and the black oxide finish offers mild corrosion resistance and lubricity. The knurled socket cap head is round with a flat top and a high profile that provides high strength, and installs using an internal drive system that enables more compact spacing than a hex head cap screw. Knurling on the head enhances grip for hand-turning. The hex socket drive, also known as an internal hex drive, has a hexagonal slot that requires an Allen key driver, also known as a hex key or Allen wrench.

Shoulder screws, also known as shoulder or stripper bolts, have a smooth shaft that acts as a spacer or bearing surface between the threaded portion and the screw head. Shoulder screws with round shafts are commonly used for items that require rotation, while those with square shafts are typically used to lock into place and prevent rotation.

Unbrako manufactures high-strength socket screws and other fasteners, including dowel pins and shoulder screws. The company, founded more than 80 years ago, meets International Organization for Standardization (ISO) standards 9001:2000 and TS 16949:2002.