SLA-TEK is the first custom formulated, molded and tuned material ever developed for turkey calls. Knight & Hale's Mini SLA-TEK friction calls are now made with this superior technology. Ol' Yeller Pocket Puppy Slate by Knight & Hale SLA-TEK was developed to produce true and natural turkey sounds. It takes little effort to make this call whisper or scream. The Pocket Puppy is a must for turkey hunting beginners and a secret weapon for the seasoned pros