The internal bag separates the urine from the pressurizing agent so there is no contamination. The system allows only 100% pure lure to be dispensed. Sprays longer than traditional spray cans, and is quieter too so it won't spook deer. Tink’s #69-X is a unique formulation developed to break down slowly and release its scent just like natural doe estrous. Tink’s #69-X is best to use during the rut. 3 oz.