Checkpoint 300 Ultra-mag G3 8-1/2-inch 4-vial Platinum Magnetic Torpedo Level with Sleeve Non-laser ultra magnetic torpedo level; water and shockproof 4 precision-aligned vials, extra-large V-groove system parallels up to 10-foot diameter Neodymium magnet system and aluminum alloy construction Lifetime guarantee Includes a carrying sleeve designed specifically for the Checkpoint 300