indeed it is a 30mm.
A 30mm ER5 Leica riflescope for the low, low price of only 530.
Brighter than the leupolds I tested it next to, not quite as bright as the Kahles, Zeiss diavari, and S&B. But those scopes are much more money for a few extra minutes of light ....... about 15 minutes past legal shooting times.