Snugpak Enhanced Patrol Poncho
The Snugpak Enhanced Patrol Poncho is a comfortable, one-size waterproof poncho. Designed to fit easily over your head and bag, this poncho can even be used as an emergency tarp should you have an unscheduled night in the hills.
The waterproofing on the poncho is a PU coating so will not need any attention to keep it waterproof, but the outer surface is treated with DWR (durable water repellent) which causes the water to bead up and roll off.
Once deactivated, it can lead to the fabric wetting out and looking like it is failing but this is just cosmetic. The DWR can be reapplied, and we would suggest something like Nikwax or Granger's products. These products are supplied with full instructions and are usually washed in or sprayed on the item.
There is no hard and fast rule as to how often you would need to do this, just when you notice water stops beading up on the garment.