This Shaft with white ( removable ) segments is made to be used for Autotrol 155 & 255 water softener control valves. Old part # 21F ( new PN 1033024 ).
Or for less money you should order our AP21F3 Black Standard One-Piece.
The length of all 155 and 255 camshafts are 6 inches ( not including the "tips" that engage the timer and rear bearing ).
NOTE: Many older systems used a White Segmented Camshaft.
Iron filter and Backwash only Camshafts are modified versions and you would need to "re-use" your "white" or "gray" segments on the shaft.
We do NOT have the segments ( cams ) separately, and we do NOT have this available for any other model besides 155 and 255.
It will NOT work the longer 163, 168 valve bodies ( nor 263, 268 ).