This thermowell is the best option for monitoring temperatures in the FermZilla but can be installed into almost any fermenter lid with a drilled 8 mm hole. It can be pushed through a bung with a 6-8 mm hole but includes the Duotight bulkhead fitting that you can use to attach this thermowell to the lid of the FermZilla or another fermenter. The FermZilla will still be pressurizable after installing the thermowell, just be careful to drill the hole no wider than needed to fit the Duotight bulkheads.