What is this ammo?

Looks like a box of 5.56 NATO manufactured in Spain, or some other Spanish speaking nation.

The SS109 is the equivalent of 62 grain, steel core, M855.

Lead core w/ hardened steel penetrator tip. Indoor ranges probably wonder you shoot it and its not a good idea to fire it at steel targets.

Alfon, SS109 is the NATO name for what the US calls M855 ball ammo. That's a 5.56x45mm / 5.56 NATO cartridge loaded with a 62 grain full copper jacket bullet with lead core and steel penetrator tip. It was introduced in the US in the early 1980s along with the M16A2 rifle. It was part of arms development during the Cold War, and it was designed to penetrate Soviet soft body armor of that era, but it's not a true armor piercing round.

It's fine as target ammo. You can also use it on small animals no bigger than fox or coyote (and smaller animals) if you're hunting them for their fur and want small bullet holes that do the less damage to their skin. Otherwise, because it doesn't reliably expand, it's not a good choice for hunting.

As for the green tip, the US and some other countries dip the tips in green paint for easy and quick identification. Several countries don't paint the tips green though.

Good ammo but if you use it at a range with a steel plate bullet catcher (as our range) you're in for a good conversation with the owner.

same goes for the bulk pack S&B ammo.
At our range we check ammo with a magnet to find out if there is any steel in the tip.