Used Halfords roof box.  Good condition.

One key only so another would need to be cut.

U bar type fittings di.ensions 80mm x 35mm as shown in photo 5 for square roof bars but it has been used on other shape bars (wing/aero) within these dimensions.

50kg max load capacity.  Guessing at approx 320L capacity based on measured dimensions and historic ads for Halfords boxes.