There are four available sizes (currently all are 45deg corners).
Size 1 corner- is the smallest corner and goes side by side with corner 'size 3', and has a 50mm gap to the 'size 4' corner.
Size 2 corner- Goes side by side with the 'size 4' corner.
Size 3 corner- Goes side by side with the 'size 1' corner.
Size 4 corner- is the largest corner and goes side by side with corner 'size 2', and has a 50mm gap to the 'size 1' corner.