the image shows red text on the inner circle with a range up to 60 psi. The black looks like it is 2.5 bar. That said it would be good to have them confirm. If they haven't answered yet there are now other options that include details.

For the brew keg specifically you’re gonna be fermenting under pressure so this allows you to dial that in. With some additional pieces you could make it a spunding if you chose to.