FlipTop® Optima Flip-Off Seals for Vials: Specifications and Sizing

FlipTop® Optima Seals, Standard Flip-Off Cap for Vials | Autofits

The FlipTop® Optima is an aluminium-plastic flip off seal for injectable vials: an aluminium shell crimped over the rubber stopper, topped with a moulded polypropylene button you flip up to expose a central injection point. It is made in 13, 20, 28, 32 and 34 mm neck sizes, in Bridge, Button and Flower designs, with glossy, matte, embossed or printed finishes, to ISO 8362-6 and ISO 15378.

This page sets out the Optima range for formulators, packaging engineers and sourcing managers: full dimensions for every size, materials and manufacturing, the regulatory and quality position, applications, how it compares with other closures, and how to order.

Key takeaways

The FlipTop® Optima is an aluminium-plastic flip-off seal in 13, 20, 28, 32 and 34 mm; 20 mm is the highest-volume size.
Three top designs: Bridge, Button (the Button design gives intrinsic tamper evidence via a 12-stem flower under the button disc) and Flower.
Finishes: glossy, matte, embossed or printed, available in a wide range of colours customised to requirement.
The aluminium shell is AA8011 alloy with epoxy lacquer; the button is polypropylene, moulded in-house on Toyo machines.
Made under ISO 9001, ISO 14001 and ISO 15378 with a Drug Master File (DMF 18100); the design follows ISO 8362-6.
Supplied Regular, Ready-to-Use (gamma or ETO sterilized) and Ready-to-Sterilize, with double-bagged options for aseptic filling.
For the closure category overview, see flip-off seals and the flip-off seal glossary entry.

What is the FlipTop® Optima and where it fits

The FlipTop® Optima is the standard flip-off seal in the Autofits FlipTop range: the everyday aluminium-plastic closure for injectable and parenteral vials. It combines a deep-drawn aluminium shell, which crimps under the vial neck flange to compress the rubber stopper against the glass, with a moulded polypropylene button on top. The user flips the button up to expose a small central area of the stopper for the needle, while the aluminium stays crimped in place and the seal integrity is preserved.

Within the wider product range, the Optima is the default flip-off design. Where the whole seal needs to come off rather than just a button, the FlipTop® Pull Ring (pull the aluminium ring, open anticlockwise) and the FlipTop® Tear-Down (twist anticlockwise to remove the seal, mainly for oral vaccinations) cover those access patterns. All three sit under the FlipTop seals family, and the complete catalogue is on the products page.

The Optima is specified by vial neck size. Match the seal size to the vial finish and the stopper of the same nominal diameter (vial necks follow ISO 8362-1). Browse by neck size from the by-size index.

Specifications and sizing

The table below gives the controlled dimensions for each Optima size, taken from the Autofits engineering drawings, together with the maximum opening force and the standard packing. Opening force varies with the number of bridges in the design.

Size	Inner Ø alu seal (D1, mm)	Outer Ø disc (D2, mm)	Disc height (mm)	Inner alu height (mm)	Total seal height (mm)	Alu thickness (mm)	Bridges	Max opening force (N)	Standard packing (per box)
13 mm	13.36 (min)	14.99 (max)	2.90–3.30	6.15–6.40	7.62–8.38	0.16–0.20	6 taper	30	15,000 (5,000 × 3 bags)
20 mm	20.22 (min)	23.14 (max)	3.20–3.60	7.37–7.62	9.02–9.91	0.16–0.20	6 taper	35	6,000 (2,000 × 2)
28 mm	27.60–28.20	30.10–31.10	not specified	8.70–9.30	11.06–12.06	0.17–0.23	8	35	3,000 (1,500 × 2)
32 mm	32.10–32.90	35.50–36.50	not specified	not specified	14.30–15.50	0.21–0.25	12 taper	65	1,400 (700 × 2)
34 mm	33.60–34.00	35.50–36.50	not specified	not specified	15.00–16.00	0.20–0.25	8 taper	available on request	available on request

The standard shipper box is 420 × 270 × 320 mm. Tyvek bagging is available as an alternative to the standard polybag packing. The 34 mm opening force and pack quantity are available on request.

Top designs and finishes

The Optima top is offered in three designs:

Bridge: the standard flip-off button connected by tapered bridges that shear when the button is flipped.
Button: carries intrinsic tamper evidence, with a 12-stem flower formed under the button disc, so the opened state is visibly distinct.
Flower: the petalled top variant within the Optima range.

Finishes are glossy, matte, embossed or printed. The seals are available in a wide range of colours, matte or glossy, customised to requirement; colour coding is commonly used to differentiate products and strengths. Contact us for colour matching against a reference.

Materials and manufacturing

The Optima is an aluminium-plastic closure: an AA8011 aluminium shell with epoxy lacquer and an injection-moulded polypropylene button. Each material is selected and tested for parenteral packaging duty.

Aluminium: alloy AA8011, conforming to EN 15088:2005, supplied with EN 10204 3.1 certification and tested to BS EN 485-2:2008. REACH and RoHS compliant.
Lacquer: epoxy lacquer coating conforming to 21 CFR 175.300, double-lacquered for the Ready-to-Use form; it may be pigmented for colour.
Button: polypropylene (PP) conforming to IS 10910 / IS 10909 and FDA 21 CFR 177.1520 (olefin polymers), with EC 1895/2005 compliance; BADGE, NOGE and BFDGE are not used.

The PP buttons are moulded in-house on Japanese Toyo injection-moulding machines, which keeps disc geometry consistent batch to batch. Components are washed on a fully automated line to control particulates, then assembled in an ISO Class 8 cleanroom. Every seal passes 100% high-speed camera inspection before packing. Production runs in the Autofits Packaging Pvt. Ltd. 75,000 sq ft facility in Nashik, India.

Regulatory and quality

The Optima is designed to ISO 8362-6 for aluminium-plastics combination caps and is produced under an ISO 15378:2017 GMP quality system. The quality and regulatory position across the range:

Design standard: ISO 8362-6 (aluminium-plastics combination caps for injection vials); see ISO 8362-6. Vial necks follow ISO 8362-1.
Quality system: ISO 9001:2015, ISO 14001:2015 and ISO 15378:2017 (GMP for primary packaging materials); see ISO 15378.
Regulatory filings: Drug Master File (DMF 18100) and CFDA registration (B20200000501).
Food-contact and material compliance: lacquer to 21 CFR 175.300; PP to 21 CFR 177.1520.
Heavy metals: chrome-VI, cadmium, mercury and lead at a maximum 100 ppm total (EN 602, EC 94/62).
BSE/TSE-free: per EMEA/410/01 rev. 3.
AQL: critical defects nil; major defects not more than 2.5%; minor defects not more than 4%. The AQL plan is tailorable to customer specification.

The full certification set is on the quality page.

Applications

The Optima is the general-purpose flip-off closure for injectable and parenteral vials across the size range. Typical uses include:

Liquid and lyophilised injectables in 13 mm and 20 mm vials, the highest-volume neck sizes.
Larger-volume parenterals, diluents and infusion-style vials in 28, 32 and 34 mm.
Products that rely on colour coding to differentiate strengths or presentations.
Lines that require tamper-evident closures, where the Button design provides intrinsic tamper evidence.
Aseptically filled products that need sterilized, ready-to-use seals delivered double-bagged.

Match the seal to the vial neck and stopper of the same nominal size. Browse the by-size index to confirm dimensions against your vial finish.

Comparison with alternatives

All four closures crimp an aluminium shell over the stopper; they differ in how the vial is opened and whether a plastic top is present.

Closure	How it opens	Plastic top	Typical use
FlipTop® Optima	Flip the plastic button, exposing a central injection point	Yes (PP button)	Routine injectables; colour coding
Pull-Ring	Pull the aluminium ring, open anticlockwise; whole seal detaches	Yes (PP disc)	Where the whole seal must come off
Tear-Down	Twist anticlockwise; the seal tears down and off	Yes (PP disc)	Mainly oral vaccinations
All-aluminium tear-off	Tear the metal top away	No	All-metal closure, fuller stopper access

For the flip-off versus tear-off distinction in detail, see flip-off vs tear-off seals.

Forms of supply and ordering

The Optima ships in three forms to match your fill line: Regular, Ready-to-Use and Ready-to-Sterilize.

Regular: non-sterile seals for customers who sterilize in-house or run terminal processes.
Ready-to-Use (RTU): assembled in the ISO Class 8 cleanroom, double-lacquered aluminium, washed to control particulates, then gamma irradiated or ETO sterilized, supplied double-bagged for aseptic areas.
Ready-to-Sterilize (RTS): cleaned and bagged for the customer’s own sterilization step.

Sterilization is by gamma irradiation or ETO. Shelf life is 3.5 years before capping for non-irradiated seals (plus 5 years after capping), and 2 years before capping for RTU. Tyvek bagging is available where required.

Colours, finishes and the Bridge, Button or Flower design are specified per order. For minimum order quantities and lead times, contact us with your size, design, finish, colour reference and required form of supply.

FAQ

What is a flip-off seal?

A flip-off seal is an aluminium-plastic vial cap: an aluminium shell crimped over the rubber stopper with a moulded plastic button on top. You flip the button up to expose a small central area of the stopper for the needle, while the aluminium stays crimped and the seal stays intact. The FlipTop® Optima is Autofits’s standard flip-off seal.

What sizes does the FlipTop® Optima come in?

The Optima is made in 13, 20, 28, 32 and 34 mm neck sizes. The 20 mm size is the highest-volume option for injectable vials, and 13 mm is common for smaller-volume products. Each size has its own controlled dimensions and standard packing, listed in the specifications table above.

Which Optima design gives tamper evidence?

The Button design carries intrinsic tamper evidence: a 12-stem flower is formed under the button disc so the opened state is visibly distinct. All flip-off seals show that they have been opened once the button is flipped, but the Button design makes the evidence intrinsic to the closure.

What materials is the Optima made from?

The shell is AA8011 aluminium alloy with an epoxy lacquer coating to 21 CFR 175.300. The button is polypropylene conforming to 21 CFR 177.1520. Heavy metals are held to a maximum 100 ppm total, and the components are BSE/TSE-free per EMEA/410/01 rev. 3.

Are the seals supplied sterilized?

Yes. The Optima is available Ready-to-Use, sterilized by gamma irradiation or ETO and supplied double-bagged for aseptic filling, as well as Ready-to-Sterilize for your own sterilization step and Regular (non-sterile). RTU seals are assembled in an ISO Class 8 cleanroom and washed to control particulates.

What standards does the Optima meet?

The design follows ISO 8362-6 for aluminium-plastics combination caps, and the seals are produced under ISO 15378:2017 GMP, with ISO 9001:2015 and ISO 14001:2015 certification, a Drug Master File (DMF 18100) and CFDA registration. See ISO 8362-6 and ISO 15378.

What is the minimum order quantity?

Minimum order quantities and lead times depend on size, design, finish and form of supply. They are available on request; contact us with your specification and we will confirm MOQ and lead time.

Can you match a specific colour?

Yes. The seals are available in a wide range of colours, matte or glossy, customised to requirement, and can be embossed or printed. Send a colour reference and we will match against it; exact colour lists and codes are confirmed per order.

Sources

Autofits FlipTop Seals dossier and engineering drawings (working/spec-sheets/)
ISO: ISO 8362-6:2010, Injection containers and accessories, Part 6: Caps made of aluminium-plastics combinations for injection vials (https://www.iso.org/standard/45641.html)
ISO: ISO 15378:2017, Primary packaging materials for medicinal products, GMP requirements (https://www.iso.org/standard/70845.html)

*Last updated: 2026-06-26. This page is general technical and product information, not regulatory or compliance advice; confirm current standard editions and your own specification with Autofits and the issuing bodies.*