Please note that this receiver is an estate sale item and being sold as-is and untested, making it essential for the buyer to carefully assess its condition before use. I was unable to open the battery compartment as it seems to require more pressure than I was able to exert. Sold as-is with no return option.This is an estate sale item, sold untested. Unit comes with snap-on collar. The PetSafe Gentle Spray Anti-Bark Collar safely and quickly conditions your dog to stop barking using a harmless burst of spray. The collar uses a microphone to pick up your dog?s bark, which triggers a harmless burst of spray. The spray interrupts your dog's barking, allowing you to redirect your dog's attention. More Info To refill the collar, make sure the unit is turned off. Hold the refill spray can upright and firmly press the nozzle down into the refill port. Hold for 15 seconds or until unit is full, then remove the can. If spray leaks out, you may need to press harder to complete the seal. Features Reduce Excessive Barking - Uses a burst of citronella spray to discourage barking; unscented spray refills also available Water Resistant - Suitable for light rain or wet grass exposure Lightweight - Designed for dogs over 6 lb with neck sizes up to 24 inches 300-400 Sprays Per Can - Each refill for collar holds 25-30 sprays Model Numbers PBC00-13912 | SNS-BK-C | DSP00001 | 300-2559