Oh, the question asked was for the Misti Corners tool. What I have use of it, I really like it.
The "L" shape is 6.5 X 3.75 inches
The (2) small corner pieces (with 2-magnets on each) are 3 X 3 inches.
The long side triangle is 5 X 3 inches
And the triangle is 4 X 4 inches and the longest side on it is 5 inches.
The magnets on the 2 small corner pieces are really strong, DO NOT let them near each other!
These guides are really nice. I am still getting use to having them! I keep forgetting about them!π
They do help to keep things lined up nicely, while stamping.
Hope this helps you.