Zenitco Stock Adapter (Butt Lock) for PT-Series Stocks

Overview

This is the lock that ties a PT-series stock to the carbine. The PT-1, PT-1S, PT-3 and PT-3S share one stock interface, and the lock is what adapts that interface to a particular platform - which is why it is sold on its own, and why picking the right version matters more than anything else on this page.

The choice comes down to the hinge pin diameter and to whether the platform allows operation with the stock folded: 4.5 mm for the short-barrel U variant, 5.5 mm for AK-pattern carbines that fire folded, 5.5 mm for civilia carbines built on that platform (folding only), 5.5 mm for Saiga-9 and TR9 Paradox, plus a non-folding 5.5 mm version. Changing the lock later is a single screw.

Overview

This butt lock is the interface that mounts Zenitco PT-series stocks (PT-1, PT-1S, PT-3, PT-3S) to an AK-pattern carbine. It replaces the factory stock attachment and locks the Zenitco stock into place for a solid, repeatable connection.

The correct adapter type depends on the carbine: for AK-pattern the stock-axis diameter is 4.5 mm, while duty AK-pattern variants with fold-and-fire capability use their own fitment. This part is the AK-pattern version, machined from steel for durability.

Technical Specifications