Bolt carrier and telephone: what they have in common

1. Step 1. Bolt carrier — is part of — Assault rifle. It reloads the weapon.
2. Step 2. Assault rifle — has part — Spring. A return spring.
3. Step 3. Spring — is part of — Rotary dial. A return spring.
4. Step 4. Rotary dial — is part of — Telephone. A dial.

Open Evothings