Rainier Arms Extended Take Down/Pivot Pin Set AR-15 Black. Specifications for Rainier Arms AR-15 Extended Take Down/Pivot Pin Set: Manufacturer: Rainier Arms Fabric/Material: 17-4 PH Stainless Steel Weight: 0.53 oz Gun Make: AR Platform Gun Model: AR-15 Package Contents: Rainier Arms AR-15 Extended Take Down/Pivot Pin Set What firearm models does the manufacturer say Rainier Arms AR-15 Extended Take Down/Pivot Pin Set is compatible with? The manufacturer says that Rainier Arms AR-15 Extended Take Down/Pivot Pin Set is compatible with AR-15Rainier Arms RA005-BLK: Extended Take Down/Pivot Pin Set AR-15 Black