how do you get cod spawners?

[BliepMonster]

I've seen people buy cod spawners at pwarps and I was wondering how you could get those, as they aren't available in the spawner selling npc at spawn, and also aren't available at the crates. How can you get cod spawners?

 

[Lqrenzo]

The monthly crate changes items every month. Sometimes these Cod spawners are added to this crate.