Primos Hunting Calls. The AlunmiSlate's aluminum surface easily peak at 15,000 Hz. Just as important as high frequency, the AlumiSlate also provides long-range volume. The combination of the Acrylic Striker with the AlumiSlate makes this call 100% waterproof! Includes Acrylic Striker and abrasive sandpaper. Primos Model No. 223. Primos Hunting Calls.