found this site is a bussiness but is interesting nonetheless...

[BFG Central]

I would like to know how these fix to the walls and how they release when you need to take them off, Especially if there is a need to escape quickly.
For me these would be an option as you cant see my window and doors on the ground floor from the road.
You have to get over 8ft gates and past the rotties.
But to have a third line of defense would be great as long as i could escape quickly if required, I dont fancy jumping from a first floor window.