The flat-topped polypropylene threaded closure is 53-mm in diameter, features a large milled edge for a convenient hand grip and has deep sealing screw threads. Five internal slots store up to 10 standard 1 x 3 inch or 25 x 75 mm slides back to back. The base diameter is 59.7 mm (2-3/8"), height is 114 mm (4-1/2"). steam autoclavable at 121°c (250°f), with lid detached during autoclaving. Larger opening than classic coupling staining jar for more convenient slide staining durable polypropylene construction sealing ring makes jar watertight.