I did a write up once about it :

here is the link

https://www.hdforums.com/forum/softa...with-pics.html

 

Over flushed on one side here!

 

had mine for 3 years no water problems and all the lites still work

 

I had mine for about 18 months and then the pop-up cap wouldn't pop-up any more. It was difficult to add gas when you have nothing to grab onto. All my LED's still worked but I wouldn't buy flush caps again. I replaced them with black caps that you can grab onto but still have the LED's. I have spent $400 on gas caps. Ouch!

 

If soemone didn't say so already, I would try the ones by Arlen Ness...