ATI Outdoors AR-15 223/5.56 Crush Washer 5 Pack Black One Size. 56 Stainless Steel Crush Washer pack 5 pcs Specifications for ATI Outdoors AR-15 223/5.56 Crush Washer: Manufacturer: ATI Outdoors Additional Features: Standard Included Accessories: Standard Gun Model: AR-15 Fabric/Material: Steel Activity/Occasion: Travel Work Sports Duty Outdoor Casual Hike Age Group: Adults Style: Tactical Application: Outdoor Tactical Work Casual Everyday Caliber: .223 Remington 5.56x45mm NATO Seasonal/Temperature Use: All Seasons Fit: Regular Size: One Size Quantity: 5 per Pack Gender: Unisex Features of ATI Outdoors AR-15 223/5.56 Crush Washer Premium Crush Washers Fits over 1/2-28 threads Package Contents: ATI Outdoors AR-15 223/5.56 Crush Washer What firearm models does the manufacturer say ATI Outdoors AR-15 223/5.56 Crush Washer is compatible with? The manufacturer suggests that ATI Outdoors AR-15 223/5.56 Crush Washer is compatible with AR-15ATI Outdoors A.5.10.2253: AR-15 223/5.56 Crush Washer 5 Pack Black One Size