The Hensanity™ is designed to give you tone control in all your yelps clucks cuts and purrs. Molded with tone ports simply cover or uncover to dial in the exact tone and volume you are looking for. Change it up to sound like multiple hens in a group or to find the exact sound that gobbler responds to. Pennsylvania slate surface is very responsive to all calling. – Tone holes aloow infinite range in controlling sound – Pennsylvania slate surface – One-piece striker