Solved A simply supported beam 6 meters long is 300 mm wide | Chegg.com
Shinwa 12" 300 mm English Metric Rigid (1.250 wide x .040 thick) Zero Glare Satin Chrome Stainless Steel E/M Machinist Engineer Ruler/Rule with Graduations in 1/64, 1/32, mm and .5mm Model H-3412C -
Olympus M.ZUIKO Digital ED 300mm f/4 IS Pro Review | Photography Blog