In warm weather the rubber boots get too hot, I have found. For a lab in colder weather, they are OK. I think the leather ones are the best but I would think deer skin would wear too fast. You could use it on the tops but I would use a 2- 2 1/2 oz split for the bottoms. I have used that for both tops and bottoms and it works. Make them high enough to be able to tape them. Use black plastic tape because it has some give and carry a roll with you. Carry an extra boot because he will lose one every now and then. The leather breathes. Don't forget they can't swim well at all with the boots on so when you get near H20 watch out.
