I have looked all over and there are no numbers.
Under the silo doors there is patent pending. On the underside of the head is Gilette and Made in England.
I cannot see any other markings.
Very probably Chris.
It dos feel fairly weighty and I do not trust the scales. They are only a pair of ordinary kitcehn scales so will try and find someone with some more accurate ones.
It is the colour though for me, the alu version seems very bright and this just isnt. But it might just need a fuller clean.
Anyway the jury is in with a shave this evening with it with very positive results. Good feel and direction.
The opening mech is a little stiff but I am sure it'll free off a little.