Sterling Rescue Outdoor Fly Trap, ReusableModel #: FTR and FTA How It Works The trap comes with a water soluble pouch of powder attractant. When the jar is filled with warm water and the trap is placed outdoors, the attractant dissolves and activates quickly. Simply replace the used attractant with a refill packet to allow this trap to be reused again and again. Unique Features & Benefits Fast acting attractant Just add water Simple and economical to reuse Durable plastic container holds up