The benefit of these bison tubes are the wider log sheets that are easier to handle which makes them hold up longer out in the field. Individually packaged, ready to hide. All you need to do is write up the cache page. They come in a variety colors that you can choose from, these are the SILVER ones. The regular size o-rings will fit these tubes.
Specifications: O-ring seals for waterproof Aluminum Material 2.5cm ring attached Outer size: ~1/2" x 2" 55mmx14mm Shipping Weight: 0.5 oz