The Big Bertha duck call is made for Wide Open situations where a hunter needs some volume to attract the ducks. The mouth piece is longer than the Original Big Mamma duck call and the insert is bored out for more volume. Each insert on the acrylic calls have a spit/air flow groove to help with sticking and to release the reeds if they start to stick. Also each call is tuned with a thick single reed and we use cork in this call to maximize volume. All hand tuned by Big Sean personally. Made in the USA and 100% Satisfaction Guaranteed.