Plastic film and piston pump: what they have in common
- Step 1. Plastic film — is part of — Plastic bag. A thin polyethylene film.
- Step 2. Plastic bag — is made of — Polyethylene. Polyethylene.
- Step 3. Polyethylene — is material for — Cling film. Polyethylene.
- Step 4. Cling film — is used in — Vacuum sealer. Film.
- Step 5. Vacuum sealer — has part — Vacuum pump. A pump.
- Step 6. Vacuum pump — evolved from — Piston pump. Guericke adapted the piston pump to pump out air.