For something that’s going to be used outdoors in rain and snow, I treat with a couple of coats of good old fashioned Sno Seal. Wipe it on, and melt it in with a hair dryer. I just made a batch of rifle slings out of medium brown Hermann Oak veg tan, and soaked in Sno Seal on them. Gave them a nice rich color and the best part is that when it does get scratched up you can just wipe on more and melt it in! I’ve heard great things about Obenauf’s as well, when I run out of Sno Seal I may give it a try.