A very good handheld stapler, the classic kind, using No. 64 staples.
Why? Because:

• It doesn’t chew up the staples or jam, as other staplers—even expensive ones—do, frustrating you and wasting your time while you try to unjam them. If they jam, you have to remove the plunger, take the staples out of the inner channel, open the vertical metal front part/component—which takes force and is not easy to open at all precisely because it has jammed—then remove the chewed-up/bent staple, put the staples back into the inner channel, and put the plunger back in. Isn’t that incredibly frustrating and a waste of time? Well, with the Allegra, you avoid all that.

• It also has a rare and clever feature: on the lower “jaw,” you can see a small square metal-colored base, which is attached to the lower “jaw” with a metal clip and a little spring?
If you press the spring-loaded tab underneath this little square base with your finger, the base lifts slightly. This releases it from the lower “jaw,” allowing you to turn it 180 degrees—that is, upside down. If you don’t lift it from underneath, this square metal base is locked in place on the lower “jaw.”
By turning this little base, you change its embossed surface, and if you staple, you make a temporary staple.
Temporary stapling means that the staple holding the papers folds outward. When folded outward, the papers are held together, but if you want to unstaple them to do something—for example, to photocopy or scan just one sheet—you can pull the papers apart, and because the staple holding them is in the temporary-stapling position, that is, folded outward, it comes out very easily without tearing the paper. You do what you need to do (photocopying, scanning), and then staple them permanently: change the square metal base back in the same way I described, and it returns to permanent stapling.
Permanent stapling = when the staple bends inward, so the papers are stapled permanently. If you have stapled them this way (permanent stapling) and try to pull out one sheet because you want to photocopy or scan only that one, the paper tears around the staple point.
With this clever feature, then, you can choose either permanent or temporary stapling, depending on what you need.
See the pictures too.