Better Mounts - Shop › Custom Tube Adapter Custom Tube Adapter $20.00 Sold Out Design and make plastic adapters to allow a 1.25” frame bracket to clamp onto a 33.8mm tube. Design and make plastic adapters to allow a 1.25” frame bracket to clamp onto a 33.8mm tube. Sold Out Added! Reviews Reviewer Name Review Date Star Rating Description Posted on Etsy Product Show More You Might Also Like Quick View Frame Brackets for 1.25" Side Rails $32.99 Quick View Crossbars from $84.99 Quick View Frame Brackets for 1.5" Side Rails $34.99 Quick View Spare Oarlock Nut and Washer $3.99 Quick View Side Rails from $32.50