Details: [21.93.2]providing and fixing sfrc manhole covers and frames marked with is: 12592 including setting the same to correct lines and levels in 1:3 cement sand mortar over manhole including carriage loading unloading stacking handling re-handling etc. complete in all respects to the satisfaction to the engineer-in-charge. 2. type:- extra heavy duty set (ehd-20) 560mm clear opening [21.93.3]providing and fixing sfrc manhole covers and frames marked with is: 12592 including setting the same to correct lines and levels in 1:3 cement sand mortar over manhole including carriage loading unloading stacking handling re-handling etc. complete in all respects to the satisfaction to the engineer-in-charge. 3. type:- extra heavy duty set (ehd-10) 560mm clear opening