Amazon.com : Amarine Made Heavy Duty Single Kneeboard and Single Wakeboard Combo Tower Rack for Clamped Tube Size: 2",2-1/4", 2-1/2" : Sports & Outdoors
Stealth Kneeboard and Wakeboard Rack with Rotating Mount
TCMT 3 Racks CNC Wakeboard Tower Rack CFR-WSWA-1 Oval Back Boat Surfboard / Kneeboard Holder Black - Walmart.com