Genuine "A" plus 1st motion shaft, also known as the input shaft.Last few. Fourth gear is the tooth part, this end of the shaft holds the large single roller bearing, with the lower drop gear(input gear) sliding on the outer end of the shaft. 15/21/26/30 teeth count
On the very end sits the bearing that fits into the clutch casing.
Now obsolete from Rover(last retail over £220-00) we have good USED genuine gears left at fraction of original cost(will not stock new imported gears) ...If you are about to undertake a gearbox strip down and you are using an old Haynes manual beware. When locking the gearbox into 2 gears to undo the large mainshaft and Ist motion nuts, lock your gears into 1st and 4th. NOT 2nd and 3rd as stated in Haynes manual as you could very easily strip your laygear or 2nd /3rd gear