The neck finish is fixed before the bottle is blown, and it dictates which closure will seal. Get the pairing wrong and you face leaks, stripped threads or a closure that will not run on your capper. This matrix maps each common neck finish to its closure format and application.
Neck → closure matrix
| Neck finish | Closure format | Application |
|---|---|---|
| PCO 1881 | CSD cap | Carbonated soft drinks |
| PCO 1810 | CSD cap (legacy — Delta makes no PCO 1810 closure) | CSD — legacy lines |
| 29/25 | Water cap (single-piece) | Still / mineral water |
| 48 mm | Handle / large cap | Large-format water (7 L) |
| 55 mm | Large PP closure | 5-gallon (≈19 L) returnable water |
| 32/15 | Juice / dairy cap | Juice & ESL dairy |
| 38 mm | Tamper-evident juice/dairy cap | Wide-mouth juice & dairy |
| 29/21 | Oil cap (1-piece LDPE or 2-piece HDPE+LDPE) | Edible oil |
| 42/36 | Oil cap + handle (Delta makes no 42/36 closure — confirmed per RFQ) | Large 5 L edible oil |
| 37 mm | Press-on closure | Juice & dairy (press-on) |
How to confirm the pairing
Match the neck on the preform spec to the closure bore and thread, then validate seal integrity at your line torque. Closure material follows the application — see the HDPE / PP / LDPE material guide; for the water vs CSD neck decision, see 29/25 vs PCO 1881 and water neck finishes compared.
Find the matching pair
Filter by neck finish in the Product Finder to see every preform and its advised closure, compare candidates on the Compare tool, and confirm the pairing in your Smart RFQ.