Poly Technologies AK47 Gas Block Retaining Pin Black. The barrel is notched where the Gas Block is located. To remove the gas block simply use a punch to remove the pins and free the block from the barrel. Two pins were used on some PolyTech models but only a single pin was used on the Spike Bayonet type Gas blocks. Specifications for Poly Technologies AK47 Gas Block Retaining Pin: Manufacturer: Poly Technologies Color: Black Gun Make: Kalashnikov Gun Model: AK-47 Fabric/Material: Steel Condition Quality: Excellent Condition Details: Other Package Contents: Poly Technologies AK47 Gas Block Retaining Pin What firearm models does the manufacturer say Poly Technologies AK47 Gas Block Retaining Pin is compatible with? The manufacturer suggests that Poly Technologies AK47 Gas Block Retaining Pin is compatible with AK-47Poly Technologies 70-01-33: AK47 Gas Block Retaining Pin Black