Can anybody tell me the spanner sizes of the two spanners in the toolbox . I recently got a car and only the lug wrench is inside . I have a screwdriver . Would like to put my own spanners inside there but don't know what size they are . Thanks

 

They are all open ended and are:
Larger - 12mm & 14mm
Smaller - 8mm & 10mm

By the way, the Americans call them "wrenches" :-)
Welcome to the forum.

 

Look under the hood. Both my wrenches/spanners were missing. When doing a detailed survey after purchase, I found the 12mm/14mm under the hood, wedged between the air box and shock tower.

FWIW, you need the slip joint pliers and penlight to make the kit complete.