I have obtained a grenade, No. 68 A.T. III VEC. Presumably made by Vickers Engineering Company but I stand corrected on that detail. The disc that is retained by the cap, which is usually brass, is, in this case, steel. There is not a sign of any paint ever having been applied to the outside surfaces. The main point of my post is that the Gas Check Plate, which is usually held in place with a set screw, on this one is held in place by the rear fin casting. It would appear that a round boss is cast in the middle of the fins, the GCP is placed over it and the Mazak material rivetted over as per the pic.
I have not seen this type of assembly before but having said that quite often the rear face of the GCP is not the detail shown! Was this a cheaper assembly method for later in the war for display training samples, or was it a cheaper method early in the war that they found to be less than successful and then went to a set screw fixing? I know a some stage they had integrally cast fins and GCP's.
Finally at thi spoint, does anyone know what the correct markings are on a No.68 grenade ammo box. I have the correct one but no markings?

Finally at thi spoint, does anyone know what the correct markings are on a No.68 grenade ammo box. I have the correct one but no markings?