Designed to open Rolex Oyster cases.  The six tempered rings will fit every existing size and because they are precision made to interlock, they will not slip.  The sturdy cast frame fits into your bench vise and the small bar gives you the torque you need for stubborn case backs.  The built in adjustable case holder fits all size watches.  Ring sizes are 18.5, 20.2, 22.5, 26.5, 28.3, 29.5mm.
 

Waterproof Case Wrench

Modeled after the famous JAXA, but less expensive, this case wrench meets the highest standards at a moderate price.  Packed in a hardwood box.  5 1/2" length.