All cases contain custom cut Polyethylene Foam. This foam has a closed cell structure which makes it virtually impermeable to water and is highly resistant to water/odor transmission. All materials will be placed in Nylon Storage Bags and/or glass jars.All cases contain custom cut Polyethylene Foam. This foam has a closed cell structure which makes it virtually impermeable to water and is highly resistant to water/odor transmission. All materials will be placed in Nylon Storage Bags and/or glass jars. The kit includes vital materials for effective K9 training.