HS Strut Introduces the Cobb Series mouth diaphragms a Hunter's Specialties exclusive. Designed by long-time HS Strut pro staffer Steve Cobb this custom line of aluminum frame calls pays homage to his more than 25 years of experience developing the highest quality calls at the highest level imaginable for the HS brand. these unique cuts and combinations were created with dedicated spring turkey hunters in mind and a little twist to make each call not only extremely true-to-life but also incredibly easy for users to run and master.