Never needs a refill because you charge it with the included pump.Never buy another refill! This air horn produces more than 50 115db sound blasts per charge. And, it emits air instead of other propellants, so its environmentally friendly. Recharge with the hand pump. Meets USCG sound-producing regulations. Type: Portable Maximum Decibels: 115db Overall Size: 5" x 8" USCG Approval: Yes