Allen CSK

Flat head screws are used for flush mounting of sections, usually where one part slides over another or one part is mounted on another. Countersunk head screws, like button heads and low heads, are limited by configuration in their tensile strength capability.  Because of this, they should not be used in applications requiring full strength, where Socket Head Cap Screws should be used.

The head angle for metric countersunk socket screws is 90 degrees up to & including M20 and 60 degrees over M20. The head angle for Imperial is different – Unified is 82 degrees and British thread forms are 90 degrees.

Usage : Machine Guards, Hinges, Covers, multiple level assemblies etc.

Available in Hexagonal socket drive and the improved 6-Lobe (Hexalobular) drive.

Allen (Hex socket) Flat Head Screws are available as per ISO 10642 (similar to DIN 7991 which is now obsolete).