• Preloaded syringe-style dye tester for detecting leaks. • Contains concentrated dye that stays underwater. • Six-inch plastic needle for precise placement. • Identifies structural leaks and water movement in pipes. • Refillable with Leakmaster Dye in 8-ounce bottles. • Active Ingredients: 97.46% Water and 2.54% C.I. Navy Blue 73. • Fill the plunger with the dye. • Locate the area of the pool where you suspect a leak. • Inject the dye into that area. • Observe the area for signs of dye escape.