The WHISTLE TIP is a blast mitigation device (BMD) for their Cherry Bomb muzzle brake. 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.
“It’s that woo woo! You know what I’m sayin’?”