What are these and how should I use them?

[Crofter]

 

My new Aluplast sliding door came with a box full of these. No instructions and the pdf I've found online doesn't really help. 

 

I was just planning on screwing through the frame prior to fitting the glazed units, but thought I'd check in case I was missing out by not using these.

[markc]

Fixing straps, fix to frame and extend inwards so you can fix without going through the frame. 1, no holes through frame and 2, the frame can “float” a bit rather than pulling it tight to masonry etc.

[Gone West]

1 hour ago, Crofter said:

My new Aluplast sliding door came with a box full of these. No instructions and the pdf I've found online doesn't really help. 

Very similar to the type I have. There should be a slot around the outside of the frame. The steel strap should be put in the slot so it is parallel with the edge of the frame and then turned through ninety degrees so that the two protruding lugs lock into the slot in the frame.