Related Clues:
- They might be cracked
- Parts of a gymnastics routine
- Burglars' targets
- Cracker boxes?
- Strongboxes commandos lined with iron
- Gymnastics feats
- Hotel's hiding places
- They’re sometimes cracked
- Heist targets
- In-the-wall security features
- Strongboxes to ship containing argon and iron
- Gymnast's jumps
- Green boxes?
- Locked boxes
- Strongboxes for valuables