RE51

The RE-51 is a preamp and EQ module for the 500-series built around the acclaimed OPA1731 vintage opamp.
Usual perks such as polarity reverse and phantom power are easily switchable,
but with recording workflow convenience in mind Lindell have also included stepped pots for each rotary controls
to ensure ease of recall between different vocalists or sessions.

http://lindellaudio.se/RE-51.php