ASG Scorpion Evo Bolt Catch Hold Open (Airsoft)

Easy to use. Just pull down the bolt catch, insert the little piece and the pressure should keep it in there nicely and keep holding down the bolt catch. Slowly release the bolt catch after insertion. If you do it too fast, the sudden pressure might push the piece out again.

To remove, simply angle the airsoft downwards and press down the bolt catch a bit more. It should fall straight out.