Thanks Chris, that seems like a good price. What are the max dimensions of the roof rack bar the J-bars fit onto?
I've been looking for something that will fit with the Thule Aero bars (curved), the top ebay t-bar claims to have a fitting to fit into the T-shaped groove within the aero bars and the bottom one can be adapted with some extra component(s) - awaiting photos. The bottom one is claimed to be dismountable (pillar unscrews?). Good for avoiding hitting garage ceilings too. Good tip - take kayak, bicycle off roof before driving into garage, multi-story car park etc.
O London, see
Swelling with naval pride, the pride of thee!
Wide, deep, unsullied Thames, meandering glides,
and bears thy wealth on mild majestic tides.