These nylon patterns are woven directly into the webbing for excellent durability. This collar is in prepunched for use with many brands of electronic containment fencing including Pet Safe, Invisible Fence, Pet Stop and Dog Guard. Dual adjustment points assure proper centering of the receiver on the dog's neck. Side release buckle is custom-designed for strength. Not for use with a leash. Four size ranges in three-quarter inch wide; three size ranges for 1 inch wide. To determine collar size, measure snugly around the middle of the dog's neck, then add an extra 5-percent for a comfortable fit. Machine wash after removing the receiver, warm water, mild soap (no bleach or bleach alternative). Air dry.