They are only useful as Rock-It Launcher ammunition. They are somewhat rare except for random placement in containers or in different creatures' bodies. A few merchants and traders such as Moira or Crazy Wolfgang will, on occasion, sell one or two. They also usually appear in grocers on a counter or in the aisles.
- 17 spread throughout Red Racer factory's factory floor.
- 11 inside Meresti Metro station.
- Eight in Evergreen Mills foundry.
- One in Willy's grocer.
- One in the Northwest Seneca Station grocer on an aisle shelf.
- One outside of the Bailey's Crossroads Metro on top of a suitcase.
Fallout: New Vegas
- Three on Vault 19's first floor.
- Two in Vault 11's living quarters.
- One in Brooks tumbleweed ranch, on the table next to the ham radio.
- One in Nipton General Store, upstairs on the nightstand next to the bed.
- Two at Ranger Station Charlie. One in the small trailer opposite the building's door, between two mattresses. Another laying inside an open locker, in the booby-trapped room to the left upon entering.
- One near the Barton the Fink encounter in a small trailer on a suitcase, across from Jean Sky Diving.
- One in The King's bedroom at the King's School of Impersonation.
- One at Wolfhorn ranch, on top of the grave near the overlook.
- One in a second floor bedroom of the Jacobstown lodge, with radio equipment next to a tipped over hula girl.
- One on the kitchen table of Hell's Motel.
The harmonica and the acoustic guitar are the only musical instruments found in Fallout: New Vegas. However, neither of them are playable.