It tightens quite a bit but in no way corners. I got 2 and both are the same; the more you tighten, the more it ruins the cornering even with perfectly cut pieces of 16mm melamine. You just tighten it, but you have to keep an eye on the cornering.

Very accurate tool
Metal corners, not plastic, brings the pitch where it should be
After all, Stanley

Very sturdy clamp and ideal for heavier tasks.
I recommend it for wood thicker than 15mm because due to its weight, it is probably difficult to use on thinner pieces.
If I have to find a disadvantage, maybe it's the weight.
I highly recommend it without reservation.

This specific stapler is perfect for woodworking. I have bought 2 of them and mainly use them for furniture assembly. You can find cheaper ones, but they are not as durable. It is worth its money.

Quite good and sturdy, it will take you a little time to find it but it does the job satisfactorily.