LEGO Technic Beams set LB gray size, 15, 11,9,7,6,5,3 (23 pieces) LEGO Technic Beams set LB gray (medium stone gray) size: 15, 11,9,7,6,5,3 (23 pieces) 5 size 15 beams, 5 size 11 beams, 1 size 9 beam, 6 size 7 beams, 2 "thin" size 6 beams, 3 size 5 beams, and 1 size 3 beam.