GENUINE WARNER LOWER HALF OF THE CLUTCH (FRICTION DISK AND RELEASE BEARING I.E THE BITS THAT WHERE OUT). It includes evrything in the photo including the  crank bolt, this is a genuine item made by warner clutches but may be packaged in John deere, hayter, or mountfeild packing depending on which suplyer is cheapest at the time of re stocking.

The clutch has 2 bolt holes on the underside where the blade or blade carrier bolt to.
It fits
HAYTER HARRIER BBC RANGE SO 41, 48 AND 56

MOUNTFEILD, CASTEL GARDEN, STIGA AND LAWNKING
M3, ,M5 AND EMPEROR 
EL63, EX70, EX80
R25M, R25V
625M, 725M, 625H 725H, 725M, 725V
534TR3S, XA55MBS, XA55MH3, 534TBXG, 534WTR, 534WTRQ 

THIS CLUCH UNIT IS USED ON MANY MORE MOWERS WITH BLADE BRAKE CLUTCHES