begin{table}[H]
  begin{tabularx}{textwidth}{XXXXXXXXXXXX}
  hline
  multicolumn{1}{|X|}{} & multicolumn{1}{X|}{Shaft Diameter} & multicolumn{1}{X|}{Max Torque} &
  multicolumn{1}{X|}{Outer Flange Diameter} & multicolumn{1}{X|}{Flange Base Depth} & multicolumn{1}{X|}{Inner Flange Diameter} & multicolumn{1}{X|}{Flange Boss Depth} & multicolumn{1}{X|}{Pitch Centre Diameter} & multicolumn{1}{X|}{Number of Holes} & multicolumn{1}{X|}{Hole Diameter} & multicolumn{1}{X|}{Key Way Width} & multicolumn{1}{X|}{Key Way Depth} \
  hline