Our Citronella Spray Refill works with all PetSafe spray products including spray bark control and spray remote trainers. Citronella is a more effective deterrent for some dogs than our unscented spray. To refill the collar, make sure the unit is turned off. Hold the spray can upright and firmly press the nozzle down into the refill port. Hold for 15 seconds and remove. If spray leaks out, you may need to press harder to complete the seal.