I need to replace one brake or tail-light bulb and they're often sold in packs of two. The spare(s) get thrown in a tray in the trunk. Previously.
Now the spare bulb(s) are protected in this carrier box. This carrier is designed for a BA15 bayonet style auto bulb.
The base and cover are designed with zero tolerance. On my printer, when I print parts like this separately the parts mate with a nice slip fit. If I print them together the cover fails to go on.