Cutter Guide

[Apecakes]

I was given this cutter guide for a gift box design. Can somebody explain to me why there are two flaps on the bottom and left side and only one on the right and top?
Which flap would be part the outside packaging?

Just making sure :icon_confused:

 

[Apecakes]

Here is a bigger image,

 

[Paul Murray]

There aren't, the 'extra fold' lines are just the dimensions. It's just a standard box with a lid.