The clamp size is 2 inch, we supply 2 rubber inserts for 1″ to 1-1/4″ inch size tubing. Stainless Steel;Adjustable Fishing Rod Holder for Rails 1″ to 1-1/4″. The 5 rod holders will clamp to your T-Top, hardtop, tower, radar arch, rail or any structure made from 2 inch tube pipe (without insert), 1.5inch-1.75inch pipe (with insert). You will have a place for you fishing rods in a safe place off your floor;Stainless Steel Clamp On Adjustable Fishing Rod Holder for Rails 1″ to 1 1/4″. It Can Adjust to Any Angle. Amarine Made 4 Tube Stainless Rocket Launcher Boat Fishing Rod Holder Adjustable. Amarine Made Stainless Steel Slide Mount Removable Fishing Rod Holder Adjustable. 4X Stainless Steel Adjustable Fishing Rod Holder Slide Mount Removable for Boat. 4X Stainless Steel Fishing Rod Holder Clamp on Rod Holders for Boat 1-1/4″- 2″. 4PCS Boat Marine Stainless Steel Fishing Rod Holder Rubber with Cap 15 Degree. 4Pcs Lower Clamp Stainless Fishing Pole Rod Holder for Boat for Rails 7/8″ to 1″. 8Pcs Sure Grip Boat Fishing Rod Holder 20°PVC Coated Steel Wire w/ Mounting Base. Triple Rod Holder Stainless Trident Outrigger Stylish Rod Holder Heavy Duty. 2Pack Stainless Steel Transom Mounted Marine Fishing Rod Holder Tournament Style. 2Pcs Stainless Steel Fishing Rod Holder Flush Mount w/ Cap and Liner 30 Degrees. 2Pack Stainless Steel Boat Fishing Rod Holder Marine Pod Flush Mount 30 Degree. 4 PCS Tournament Clamp on Fishing Rod Holder for Rails 7/8″ to 1″Boat Stainless.