Fruit Fly Traps The perfect trap for fruit flies and gnats. Simply place ripe fruit or cider vinegar inside the mason jar and screw on lid. Patented design features 5 entry holes which guide pests into the trap. Once inside, fruit flies cannot escape! Works for a little or a lot of fruit flies! Great for indoors, outdoors, kitchens, businesses, BBQs and Camping. Family-Safe! Dishwasher safe.