Custom 2-Vial Kit Boxes

Two cavities, two different problems

When the pack contains an active vial and a diluent vial, the two are usually not the same size. A 2ml lyophilised vial next to a 10ml bacteriostatic water vial is a common pairing, and a single symmetrical insert will fit neither properly.

We cut each cavity to its own component and set a wall between them thick enough that the two cannot make contact even if the box is dropped on a corner. Where the pack is symmetrical — two identical vials — the design problem shifts to preventing them from being confused with each other.

• Independent cavity sizing — Each cavity is cut to its own component rather than to an average.
• A real dividing wall — Foam or board between the two, not just a shared depression.
• Depth staggering — Where the components differ in height, cavity depths are staggered so both finish level.
• Position marking — Printed numbering or icons on the insert so the user knows which cavity is which.

Common 2-vial pairings

• Lyophilised vial plus diluent — The most frequent kit. Cavities differ in both diameter and depth.
• Two identical vials — A two-unit retail pack. Symmetrical cavities, with the differentiation coming from the vial labels.
• Vial plus syringe or needle — A straight cavity for the vial and a long channel for the syringe barrel.
• Vial plus ampoule — The ampoule needs a cradle rather than a hole, because it has no flat base.

If one component is bacteriostatic water, the diluent side of the pack has its own labelling and presentation conventions — those are covered on the bacteriostatic water packaging boxes page.

Layout and box proportions

Two vials can sit side by side, front to back, or diagonally. The choice changes the shape of the box and how the kit reads when opened.

• Side by side — The most common. Produces a wide, shallow box that opens like a small case.
• Front to back — A narrower, deeper box that posts more cheaply but presents less well.
• Staggered — Offsetting the two cavities lets a slimmer box hold two wider vials.
• With a syringe channel — Adds roughly 15–20 mm to one axis, depending on barrel length.

Whichever arrangement you choose, the outer carton height is set by the taller of the two components — the vial size reference gives the typical figures.

Materials for a kit box

A two-vial kit is heavier than a single-vial box and is usually presented rather than just shipped, which pushes most projects toward a firmer build.

• Rigid chipboard — The usual choice for magnetic and two-piece kit boxes. Square walls, no flex, premium feel.
• SBS paperboard — Suits a folding-carton kit where cost matters more than presentation.
• Kraft paperboard — A plainer look, often used for research and laboratory supply kits.
• Recyclable paper-based stock — Combine with paperboard partitions rather than foam to keep the pack single-stream.

Insert types for two components

• EVA foam with two cavities — The most secure, and the easiest way to handle two different component profiles in one piece.
• Moulded or blister tray — Each component in its own formed pocket. Useful where the two must be visible or sealed separately.
• Paperboard platform with two holes — Lowest cost, works well when both components are similar and the box travels inside a case.
• Folded partition — A board wall creating two cells; simple, recyclable and effective at preventing contact.

Where each component needs to stay in its own sealed pocket, a formed tray is the right structure — see peptide boxes with blister or moulded tray for how those are tooled.

Printing a kit box

• CMYK process — For full-colour kit artwork, including printed instructions on the inner lid.
• PMS spot colour — Keeps the kit consistent with the single-vial products in the same range.
• Inside printing — Kits benefit more than most formats — the inner lid is where sequence and handling notes naturally go.
• Insert printing — Numbering or icons printed directly onto the insert so the user knows which vial is which.

Finishing

• Soft-touch coating — Very effective on a kit box, where the customer holds the pack while using it.
• Matte lamination — The neutral default; keeps clinical designs calm.
• Foil stamping — A logo or rule on the lid of a rigid kit box.
• Spot UV — Highlights a single element without adding cost across the whole sheet.
• Emboss and deboss — Suited to rigid board; a debossed logo on the lid reads well.

Structures for two-vial kits

• Rigid magnetic lid — The most common kit build. Opens flat, presents both components at once.
• Two-piece lid and base — A lift-off lid; slightly cheaper than magnetic and just as square.
• Sleeve and tray — A drawer that reveals both cavities together; see sleeve and tray peptide boxes.
• Tuck end carton — Economical where the kit ships inside a case and presentation is secondary.

Ordering a 2-vial kit

• 1. Send both components — Not just the vials — the syringe, ampoule or leaflet too, if they share the box.
• 2. Agree the layout — We will show you side-by-side and front-to-back options with the cost difference.
• 3. Structure and quote — Build, insert and material specified and priced.
• 4. Die line, proof, sample — A physical sample loaded with your actual components.
• 5. Production — Printed, cut, assembled where required, and packed.

Artwork guidance for kits

• Decide early whether sequence information goes on the inner lid, the insert or a card — it changes the die line.
• If the insert is printed, supply that artwork on the insert die line, not the box die line.
• Keep any text near the dividing wall clear of the fold or the foam edge.
• Supply the file as print-ready PDF — 3 mm bleed, type outlined, images at 300 dpi.

Quality control

• Both cavities are fit-tested with the actual components, not with a single representative vial.
• Assembled samples are inverted to confirm neither component escapes its cavity.
• Wall thickness between cavities is checked against the approved sample.
• Magnetic closures are cycled on sample units.
• Colour, count and finish are checked before packing.

Shipping considerations

• A loaded 2-vial kit is heavier than it looks; specify the outer case to the loaded weight.
• Rigid kit boxes ship assembled and take more volume than flat cartons.
• Foam and trays are supplied ready to load.
• Nationwide delivery across the United States.