Straight to Mains LED Guide Light - Round or Square

Hello, please can you tell me the depth in the wall that's needed for these lights (2watt 105mm Square). I have 25mm deep back boxes and I want to find some low-level lights that will fit into the backbox or mount over them.
There is no depth required for these lights they are surface mounted and would cover your 25mm holes with ease.

How far do these lights protrude from the wall, i.e. what is their depth/thickness?
The depth is 28mm.

Can this be connected to a photocell and wired to a switch controlled mains socket?
Yes this fitting will work with a photocell. You would need to wire the fittings and the photocell into the same lighting circuit.

Can you change the bulbs in these when they fail or do you have to replace the whole unit
This LED light fixture would require repair or replacement of the LED by ourselves in the event of a failure. That said it does benefit from an expected life of 30,000 hours and a three year warranty.

How far does this need to go into the wall?
This is surface mounted, No cut out is required.

Hi, Does the Led driver fit within the light casing to allow a flush fit to the wall without having to cut out additional space behind the light to fit driver etc. ? Thanks
The LED driver is integral to the fitting. The fitting sits flush to the wall and is surface mounted.