Primos early bird box call is a double-sided box creating tones only purple heart can offer that look and feel as good as it sounds. Purple Heart is one of the most durable and sturdiest woods in the world. Not only is it exotic and rare due to its beautiful color but is also water-resistant. For easy yelps no extra pressure is needed with its paddle just drag it over the hardwood box and get the combination of thick lows and sharp high notes every time. This box call sanded by hand turns into two different hens so it s like getting two calls in one.