This is a right-and-left pair of trunk or boot floors for a left hand drive (LHD) XK150 (all models) with manual/standard transmission. They are made of 3/8th inch (9mm) Baltic Birch Plywood (8 ply), shaped and drilled.
Factory part numbers BD13036 (RHS) and BD15123 (LHS late).
Floors for cars with automatic transmissions are also available for the same price; see Related Products below.