A citronella spray refill that works with PetSafeĀ® Elite Little Dog Spray Bark-Control Collar. Citronella can be a more effective deterrent for some dogs than the unscented spray. To properly refill the collar, the unit must be turned off. Make sure the spray can is upright while you firmly press the nozzle down into the refill port. Hold for 15 seconds and remove. If spray leaks out during refill, you may need to press harder to complete the seal. Your pet deserves the best. Trust PetSafeĀ® to help keep your pet healthy, safe and happy.