Owner Hooks Micro Hyper Swivel- Barrel Type 4 - 180lb.. They are made from stainless steel to achieve a premium strength-to-size ratio. Rated stronger by size than virtually any other barrel swivels on the market. Specifications for Owner Hooks Micro Hyper Swivel- Barrel Type: Manufacturer: Owner Hooks Color: Black Package Contents: Owner Hooks Micro Hyper Swivel- Barrel Type Owner Hooks 5081-041: Micro Hyper Swivel- Barrel Type 4 - 180lb.