Durable Construction: Super sturdy made of polished finish 316-grade stainless steel for long life service. Easy to Clean: Made of high-quality food-safe 316 stainless steel, it will never rust, is not dim in long-term use and has maximum corrosion resistance. Use function: Allows the rod tip to follow the trajectory of the fish, ensuring the line passes freely over the roller, preventing any friction. The topside swivel portion has drain holes so it won't hold water. Dimensions: Height: 1-1/8 inches (58.5 mm); OD: 1-1/2 inches (38.1 mm). It Will fit a rod holder butt with 1-9/16 inches (39.6 mm) or smaller outside diameter. It may be used with either 30 degrees, 60 degrees, or 90-degree rod holder. Package Includes Pack of 1 Marine City 316 Grade Stainless Steel Drop-in Swivel for Rod Holder.