What are the thick red cylinders with handles (not the drumsticks) that two minifigs are holding in set 80104 supposed to represent?
Michael has answered what pieces it is, but you ask what they represent, so I'm going to offer a guess at that: Fireworks.
2I suppose that I indeed misread the OPs question. Still I think it's perfectly possible that someone unfamiliar with Technic lego wants to know more about the cilinders in this set, so I'm leaving my answer as is. Jan 24, 2020 at 13:49
9Indeed, the description of the set on LEGO.com calls this out: "Accessory elements such [...] a rocket firework inspire unlimited play". Jan 24, 2020 at 15:48
Apparently they're called skyrockets.– MastJan 27, 2020 at 14:59
Those are red technic pin connectors
A "flick missile" pin is inserted which is one one side a bar so the minifig can hold it and on the other side a stud so the pyramid element can be placed on top.
1Thanks! Great description of the parts, but I'll have to accept Henrik's answer as I asked what they represented.– GnubieJan 28, 2020 at 5:39
yes, i understand Jan 28, 2020 at 6:49