I concur with David on those points.
1. The plastic parts from 4iiii seem to crumble after two years, certainly the case with pervious plastic parts.
2. The cost of a cover and o-ring is extremely high at CAD$19.99. In fact, I got 100 o-rings online for a fraction of the cost.
3. The cost of shipping ONLY one of these covers overseas is $39 USD - on top of the price of any other shipping charges is a kind of extortion.
4. And, 4iiii does not offer other options for shipping overseas. None.