I just replaced the aft deck ladder off of my 1980 43' Viking Motoryacht with a spiral staircase. I have no need for the ladder replaced.
The heavy duty 1" inch stainless steel tubular ladder is in excellent condition with 1" inch thick plastic steps therefore no wood that is typically on these type of ladders to maintain.
The two top steps are 4" 3/4 deep and 18" wide and the bottom step is 5" 3/4 deep and 18" wide
The overall height from bottom to top of the ladder is 68" inches.