Cleans and protects the water-repellent finish on waterproof clothing, equipment, synthetic insulated garments and sleeping bags. Doubles the life of Nikwax treatments. Do not allow product to freeze.
Reddit mentions
“Yeah they just had me send it in, I’d go for it if it’s in your budget and use some NikWaxtech wash clean/waterproof it when it gets in!”
“This is not a BIFL suggestion, but some good hardshell pants will also do a better job keeping you dry overall. You can check out gear lists from mountaineering guides like IMG,…”
“Use NikWaxtech wash to clean it about as often as you would wash a hoodie (depending on how often you use it) and then when it's wetting out refresh the DWR with the NikWax…”