Bushcrafts leather is tanned specifically for heavy duty outdoor use. The slings will soften with use and will slowly absorb skin oils from your hands and arms.The only treatment Bushcrafts recommends to put on the leather is extra virgin olive oil. The cheapest extra virgin olive oil from your grocery store will work. It's inexpensive and barely has any scent if at all.Apply very light coats, 24 hours apart.Rub a small amount into the leather directly with your fingers or a towel until the leather just starts to darken. Do the front, back and both edges. Wait at least 24 hours for the oil to fully absorb between coats and then decide if you should add another. Often times, only one coat is needed. Be advised that this will darken the leather color a shade as will sunlight.Unless you want to, there is no need to spend money on fancy leather conditioners or cleaners.