LunaR has a water resistant rating of 5 ATM (50 meters). However, this rating does not mean that you can perform any activity in deep water. 

The 5 ATM rating is designed for water resistance for inclement weather and surface swimming. Some activities should be avoided to ensure safe use:

1. Never press a button or pull out the crown while it's under water. Although LunaR has double o-rings on the button shafts, you should never press a button with LunaR submerged.

2. If the back cover of LunaR is removed, the o-ring should be inspected and greased before re-assembly. The crown should be snug but not over-tightened. To retain warranty eligibility, please have LunaR serviced by a certified watch shop.

3. Although it seems harmless, shower spray can sometimes push past seals and o-rings. The increased water pressure from shower spray can affect LunaR. It is not recommended to shower with it.

4. Always make sure that the crown (for setting the time) is fully seated and pressed in when not adjusting the time. It can be difficult to tell by looking whether the crown is pulled out. Always check the crown before swimming.

5. LunaR is rated for surface swimming only. It is not rated for snorkeling, scuba diving, or diving into a pool or other waterways, or using a diving board. 

If you experience fogging under the glass or visible water, contact customer support for further instruction.