This is a stapling gun with forward action (pushing down with your hand on the gun) which takes staples of 9.5mm width and up to 14mm depth.
It can be used for several office and home tasks.
It has a viewing window so you can see how many staples are left in the gun.
Replace staples by pushing on both sides of the grey slider whilst pulling it out.
We may have some staples you can purchase or otherwise you will need to buy your own elsewhere.
For more details see this manual for a similar stapler:
https://archive.org/details/power-shot-easy-shot-5650-manual