Bees wax:

Bees wax provides an excellent barrier to water if it can be applied to seams and made to adhere to the leather.  SNO-SEAL bees wax developed especially for heavy waterproofing and protecting all Hiking-mountaineering, Cross-Country Skiing boots. Golf, Soccer Shoes. Hunting, Fishing. Workmen's Footwear.

NOTE: This item has shipping restriction. If selected will not be shipped by air or Outside U.S. or to a military base.