The system was specified as a 200 ml frosted glass outer on a stock mould with a removable food-grade PP inner cup, one glass shared across 4 SKUs differentiated only by cup colour matched to the brand's Pantone references. The engineering sits in the cup: engagement and release force inside a band over 100 cycles on 20 samples, cup-to-outer seal held inverted at 5 °C and 40 °C, and a 48 °C / 30-day hold of the cup resin in the actual cream. Because the glass is shared, its minimum is spread over four SKUs; the per-colour cup minimum is the real floor. On a stock outer the programme runs 40–55 days. Status: scoping-stage notes; quantity, lid and decoration were still to be confirmed by the brand.
The brief
The enquiry came through the cream-jar product page, category selected correctly, and it read like a specification rather than a question: outer jar in frosted glass; inner container a removable plastic refill cup of 200 ml; cream filled into the cup, not the glass; glass jar reusable; four SKUs on the same glass with four inner-cup colours. It asked one thing — do you have this type of jar — and the honest answer is that this structure is standard for prestige skincare and spa lines, and that the interesting work is in the cup.
A 200 ml jar is a body-cream or hair-mask size, which fits a spa range, and the commercial idea is sound: one glass component across the line, differentiation carried by a cheap moulded part, and a refill business in which the customer keeps the glass. What the brief did not yet contain was quantity, lid, decoration position, fill and sale markets, or a timeline — the five things a quote depends on, and the five questions sent back.
What we specified
A refill jar is judged as a set: outer, cup and lid together. The specification below is what was drawn up for the partner factories before any quote, following the format on our refillable packaging page.
| Element | Specification | Why it is written this way |
|---|---|---|
| Outer jar | 200 ml nominal, frosted high-flint glass, wide-mouth screw neck, stock (public) mould | A shared outer across four SKUs only pays off if it needs no tooling; frosting stops below the thread root |
| Frosting | Acid-etch or sprayed frost, to be chosen against the brand's sample | Two processes, two costs, two looks; bright-spot limits per the glass QC table |
| Inner cup | Food-grade PP, removable, capacity written as nominal and brim-full with headspace | The cup is the only contact material; its brim-full and fill-line are what the filler sees, not the glass |
| Cup colours | Four, masterbatch-matched to the brand's Pantone references | Each colour is a separate moulding run; colour judged against a chip under D65 |
| Cup engagement | Click or twist geometry drawn to the outer's bore; force band specified as a range on the drawing | Firm enough to hold inverted, light enough to release by hand; the band applies to every later resin lot |
| Seal | Cup-to-outer seal plus inner disc liner under the lid | Confirms the cup seals against its own lid, not only against the outer |
| Lid | PP with liner, aluminium, or bamboo-look — to be confirmed | Largest single lever on both look and cost; decoration position depends on it |
| Compliance | Food-contact declaration on the PP cup; packaging heavy-metals ≤100 ppm | EU-bound refill cups need the declaration; the glass never touches the cream |
Capacity is specified on the cup, twice — nominal and brim-full — because a filling line quoted brim-full runs short; the rule is on the glass specifications reference.
MOQ and route
The brand's four-SKU idea is exactly the right way to think about minimums on a refill system, because the components carry different floors and only one of them is shared.
| Component | Route | Indicative minimum (partner-factory practice) | How the four SKUs share it |
|---|---|---|---|
| Frosted glass outer | Stock mould, frosted; no tooling | Low thousands for a stock glass run; ~2,000 if screen-printed | One run covers all four SKUs — the floor is spread four ways |
| PP inner cup, per colour | Stock cup if the bore matches; otherwise a cup tool at roughly USD 3,000–10,000 | Per colour: a moulding run plus masterbatch set-up — quoted per colour, not per system | Four colours = four runs; this is the real floor of the project |
| Lid | Stock PP or aluminium | Stock; custom tone or plating ~10,000 | Shared across all four SKUs |
| Decoration | Screen print or hot stamp on glass or lid | From ~2,000; ≈USD 0.014 per colour, ≈USD 0.055 per design | Shared if the mark is the same on all four |
| Own glass shape | New glass mould | 30,000–200,000 furnace floor; ≈USD 555 per cavity | Not recommended at launch volume |
The advice given: do not let the cup colours be quoted as four unrelated items. Buy the cup as one programme in four colours, and buy cup and outer from the same source so the bore tolerance is theirs to hold. Routes are in sourcing refillable packaging from China and the MOQ index.
Tests
A single-use jar is opened once. A refill outer is opened, emptied and re-engaged for years, so the interface is qualified before the golden sample, using the battery on the 100-cycle engagement test.
- Cup engagement and release — force gauge, 100 cycles on each of 20 samples; force stays inside the drawing band across all cycles; no cracking of the click feature.
- Cup-to-outer seal at temperature — filled system held inverted at 5 °C and at 40 °C; no leakage, no gap. A fridge and a warm bathroom are the real service range.
- Inner-lid seal — colour-water test at −0.06 MPa for 5 minutes; no dye outside the seal area.
- Formula compatibility on the cup — PP cup in the actual cream at 48 °C for 30 days beside ambient and cold controls; no discolouration, odour, swelling or cracking. Tested on the cup resin, never on the glass, because the glass never touches the product.
- Colour and drop — four cup colours against their chips under D65; drop from 76 cm to 1.5 m with the glass in its carton, and the cup must still click afterwards.
Timeline
- Stock outer and stock cup samples — 7–10 days, to confirm the outer and the bore before anything is coloured.
- Interface qualification — 100-cycle and 5 °C / 40 °C tests run in parallel with frosted outer samples.
- Compatibility hold — 48 °C for 30 days; the long pole, started as soon as cup samples exist.
- Golden sample signed as a set — outer, four cups, lid; production only after signature.
On a stock outer the whole programme is 40–55 days at the factory gate; a fully custom outer adds 45–60 days of glass tooling and runs 90–110 days. Apply the ×1.3 buffer and the Chinese New Year allowance from the production calendar.
What the brand learned
- The cup is the product. Capacity, compatibility, engagement and seal all live in the PP cup; the frosted glass is a reusable shell.
- Share the expensive part, vary the cheap one. One stock glass across four SKUs is the right structure — as long as the four cup colours are bought as one programme.
- Answer five questions before asking for a price. Quantity per SKU, lid, decoration position, fill and sale markets, timeline. Without them a "price" is a guess.
- Buy cup and outer from one source. Bore tolerance is the failure point of every loose refill jar.
Formats: cosmetic jars; programmes: sustainable and refillable, skincare packaging.
Vella is a Guangzhou-based beauty packaging solutions provider — a sourcing partner working with vetted partner factories operating to ISO 22716 / GMP. On a refill system we write the force band, seal temperatures and compatibility hold into the specification before any cup is moulded, and buy the outer and the cup from one source so the fit is one factory's responsibility. Draft your own spec first with the Packaging Spec Builder.
Frequently asked
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