Presma Adjustable Low Profile Gas Block, 0.625” Black Steel

The Adjustable Low Profile Gas Block, 0.625” Black Steel (GBA625) is built for AR-15 rifles using .223/5.56 pencil barrels with a 0.625″ diameter gas journal. Its adjustable gas system allows shooters to fine-tune gas flow for improved reliability, reduced recoil, and optimized performance—especially useful for lightweight or suppressed builds.

Manufactured from high-strength steel and finished in a durable black coating, this gas block delivers long-term durability while maintaining a compact footprint. The low-profile design ensures compatibility with most free-float handguards without interfering with rail clearance.

Precision-machined for a secure fit, this gas block installs using set screws and includes all required hardware for straightforward installation.

Features

• Adjustable gas system for precise tuning

• Fits 0.625″ diameter AR-15 pencil barrels

• Compatible with .223/5.56 calibers

• Low-profile design for use under free-float handguards

• Steel construction with black finish

Includes

• Adjustable gas block

• Roll pin

• Mounting screws

• Hex wrench

Dimensions

• Height: 1.35″

• Width: 0.785″

• Length: 0.99″

This adjustable .625 gas block is an excellent choice for builders seeking precise gas control on lightweight AR-15 platforms without adding unnecessary bulk.