Tajima, the name in contractor quality chalk boxes has just designed this new patent pending Jam Free Design Chalk Box with 100' of Premium grade 1mm braided nylon/polyester line. Positive-locking, gasket-sealed fill cap and extra wide fill neck. Thumb -actuated line lock hold, releases automatically during rewind. Thick elastomer cover protects the case and ensures non-slip performance. New felt gear case gasket to better protect gears from abrasive chalk. Sure grip elastomer wrapped end hook. End Hook Stay helps prevent tangles in pouch or tool box. Stainless steel pin reduces friction and increases the life of the line. Folding crank and 5 gear fast-wind for smooth dependable rewinds. Larger chalk capacity (3.5 oz)