Professional-Strength Guardian GearDouble-Layer Nylon Collars for Larger Dogs These 1 wide collars are our strongest ever providing protection and firm control over even the biggest dogs. Two layers of tough nylon are stitched together and bar-tacked at the corners so they never wear out. Collars have all-metal hardware to stand up to hard use. Each collar is fully adjustable for a comfortable fit. Matching Double Layer Nylon Leads are also available and sold separately (see item TP528) . Double Layer Nylon Colors are available in the colors and sizes listed below. Colors and sizes may be combined for quantity discounts.