ECHO CALLS INC Timber Double Reed Smoke Gray Polycarbonate Molded. These calls are made from a hard bullet proof plastic called PolyCarbonate. These calls are designed especially for close-in calling. They are very easy to blow and produce a sound that is irresistible to ducks Specifications for ECHO CALLS INC 77750 Timber Double Reed Smoke Gray Polycarbonate Molded: Manufacturer: Echo Calls Color: Smoke Gray Fabric/Material: Polycarbonate Species: Duck ECHO CALLS INC 77750 Timber Double Reed Smoke Gray Polycarbonate Molded