Lazer has been making helmets in Belgium since 1919 and they've packed a lot into its basic O2 model.
It's not loaded with vents but each opening has a big cavern on the inside of it which helps the hot air convect out at low speed. There's little in the way of internal channelling though, so there's no through breeze to help when you're going harder. And deep pads in the crown tend to suck up and store sweat, which isn't pleasant once it's chilled.
The fixed position peak does its eye-sheltering job okay though, and the deep back and adjustable cradle give a secure, protected feel. Despite a 'one size fits all' shell, it doesn't wobble too badly on smaller skulls, either. There's no reduced price crash replacement scheme though, so you might want to consider a different helmet in this price bracket.