de Havilland Lostock Prop Part

I have been cleaning this part up. It weighs a couple of kg and  6 inches in diameter.

Comprises a Bronze body, locking nut, a larger internally threaded  nut and  a  central steel threaded nut with rubber insert with retaining cicrclip.

All  marked with DHL stamps: 

Bronze Body  marked internally with BB6564/P22561/6 BE10 MTG and CF31163 on rim

Retaining Nut stamped T ;  DHL and and P225281

Large Nut marked with BEMT?03 P33302 DHL271

Inner steel/rubber P33303 as well as  <- increase;  1 turn 1.25 o ; decrease -> and A7.

So definitely made by De Havilland at Lostock  and P numbers suggesting Prop but I cannot see any similar parts on other hydromatic props and nothing like the Heron cam and dome I had before.

Contrarotating ?