Fairey Aviation Ltd – mystery "Inner Glass" cases

A colleague at work has in his possession around half a dozen wooden boxes, each around 27 x 29 x 6 inches. He was told they contained cockpit windows for a Meteor. However if you look at the labels on the box (see below) the parts are made by Fairey Aviation and were sent to Royal Navay Stores Depot Llangennech. The main label has a faint date stamp of 1953 and they are described as inner glass. This particular one is intact, i.e. unopened with the original metal straps round it. The three photos show the labels. He got them from some man who wanted to build a cold frame with them!

He’s going to bring in an opened crate, but he says they are triangular in shape, but I’m not sure of the size until we see one.

Does anyone have any ideas, does the contract number mean anything to anyone?

Apologies for the picture quality as they were taken on a mobile.