Tiger Rock A2 Spacer to Convert A1 to A2 Fixed Stock Black. It does not include the buttstock screw. Specifications for Tiger Rock A2 Spacer to Convert A1 to A2 Fixed Stock: Manufacturer: Tiger Rock Color: Black Finish: Anodized Fabric/Material: 6061-T6 Aluminum Gun Model: AR-15 Gun Type: Rifle Quantity: 1 Features of Tiger Rock A2 Spacer to Convert A1 to A2 Fixed Stock: Mil-Spec Length: 1.0625" Package Contents: Tiger Rock A2 Spacer to Convert A1 to A2 Fixed Stock What firearm models does the manufacturer say Tiger Rock A2 Spacer to Convert A1 to A2 Fixed Stock is compatible with? The manufacturer suggests that Tiger Rock A2 Spacer to Convert A1 to A2 Fixed Stock is compatible with AR-15Tiger Rock A2SPACER: A2 Spacer to Convert A1 to A2 Fixed Stock Black