The fsa grossamer sl 282 seatpost fsa39s high tech manufacturing processes let us bring the 6061 t6 aluminium afterburner stem in at a low 144g very light for a mid range stem the raw material is 3d forged and then cnc machined into the final shape fsa grossamer sl 282 seatpost features material al6061 tube with forged alloy head clamp 1 bolt nano adjust saddle clamp for simple set up finish sandblasted black with polished black anodized setback