The Knight & Hale Demolition Crew Pro Pack is precision built from custom-blended materials. Designed by professional hunters and calling champions Steve Stoltz, Kerry Terrell, and Keith Wahlig. The 3-reed Sweeper produces a high-volume, raspy, double note yelping. The Terminator is a 3-1/2-reed for mid-raspy sounds and great for cutting. Warlock has 3 reeds and is perfect for soft, seductive yelping.