A few years back I learned the hard and costly way that Compass repair is not a do it yourself proposition. Yes there are screws and gaskets and the units can be disassembled and reassembled but the reality is that the casings are frequently distorted and will not seal properly. A good compass repair place will test the tolerances in the casings and will conduct a pressure test over a few days to insure against leaks. The thing is that once you replace the glass because it was cracked or scratched, the magnetic dial because the marks had faded and then the casings you might as well purchase a new one. In my case I went against the sound advice of the Ritchie rep to get the work done by a an authorized tech service and basically forced him to sell me the parts I thought I needed. I got a new glass and all the "O" rings and gaskets and even ordered their compass oil. I put the thing together with no air bubbles and no evidence of a leak. Within a week I had an air bubble the size of a dime and within a month the size of a quarter. After a couple of months it was worst than before. Lesson learned.They have most parts available for the do it yourselfer if you want to go that route.