Fabrik Firenze is a gay cruise club, in an old factory. It's a 18+ men only gay cruising place, with different theme nights throughout the week.
Membership card “ARCO” (the national gay Association of Italy) is compulsory to enter. You can get one at the door, a picture ID is needed.
The venue is located in Calenzano. See their website for instruction on how to get there from Florence.