The CSR Precision picatinny quick detach scope rail is a medium height (26.80mm) rail that fits all SIG SG55X models without a welded on rail.
The spring loaded pin (13kg) ensures the scope sits tight and holds zero, even after you have removed and re-installed your scope/rail setup.
The rail is CNC machined from 6060 aluminium, the centering front lip and spring loaded pin on the rear end are made from steel.
Made in Holland