Most advice about IP ratings for marine electronics is dangerously incomplete. 

Boaters hear "IP67 or IP68" and think the job is done. This is a huge oversight, and it’s why countless "waterproof" boat lights fail long before they should. They aren't failing from being dunked in a bucket of water, but from the relentless assault of salt spray, humidity, and UV rays. 

A high IP number is just the beginning; true durability comes from designing for the entire marine environment. A specialist company like T-Top Lights gets this, building its entire product line around the understanding that the sea attacks electronics from every angle, not just through submersion.

Can I just use any 'waterproof' LED strip for my boat?