Slot Cars and model railroadings; "HO Scale" Model slot cars such as AFX, Lifelike track and Parma. Pages in category "Extensions". Train Slots · Hyperloop Era · Dieselisation · One- Click-Unload · Rails · Second Station · Storage · Resend · Depot Slots. Depot Slots determine how many trains a player can store in the depot. Depot slots are useful.