An aluminium low-profile gas block for M4 replicas and derived types or for other weapons with a similar diameter of an outer barrel. It's possible to combine this gas block with a free-float handguard.
Although this complement won't affect the performance of your weapon, it's necessary for those who want to keep their weapon realistic after replacing the handguard.
You can set it to your weapon by 2 allen screws, which are included in the package. Not suitable for real firearms.
Inner diameter: 18,9mm