Q XL Whistle Tip Blast Mitigation Device 338 Caliber 8.6mm QD 1.85in Copper. It also serves as a Cherry Bomb thread protector for the poors who don't / can't own a silencer. As you've come to expect the WHISTLE TIP features a taper mount for proper alignment to the Cherry Bombs and installs with any off the shelf 1-inch wrench. Specifications for Q XL Whistle Tip Blast Mitigation Device: Manufacturer: Q Caliber: 8.6mm Blackout Length: 2.53 in Weight: 4 oz Fit: XL Cherry Bomb Brake Finish: Copper Gun Model: Universal Condition: New Color: Brass/Copper Projectile Caliber: .338 Caliber Diameter: 1.38 in Gun Make: Universal Package Contents: Q XL Whistle Tip Blast Mitigation Device What firearm models does the manufacturer say Q XL Whistle Tip Blast Mitigation Device is compatible with? The manufacturer suggests that Q XL Whistle Tip Blast Mitigation Device is compatible with UniversalQ ACC-WHISTLETIP-XL: XL Whistle Tip Blast Mitigation Device 338 Caliber 8.6mm QD 1.85in Copper