Aluminium cap, black, 18 mm

Aluminium cap, black, 18 mm

This is a screw cap made of aluminium with a sealing insert made of EPE (expanded polyethylene), which closes bottles and vials with an 18/410 neck. It is used where the contents need to be reliably sealed while also achieving a clean, matte metallic appearance at the neck — typically with serums, oils, tinctures and tonics in smaller volumes. The black matte finish is understated and pairs well with both clear and coloured bottles.

The cap is suitable for aqueous, alcoholic and oil-based contents that only require simple sealing and re-opening — that is, where neither a dropper nor a spray applicator is needed.

Why this cap

• Aluminium with EPE insert – the metal holds its shape and gives the neck a solid appearance; the expanded polyethylene insert ensures the seal: when tightened, it presses against the neck rim and prevents leakage as well as air ingress.
• 18/410 thread – a standardised size, so the cap fits any bottle with the same neck type without modification.
• Black matte finish – a neutral look that does not compete with the label or the contents, and suits both clear and coloured glass.
• Easy re-sealing – the screw mechanism handles everyday opening and closing.

Use in formulation and filling

The cap is suitable for bottles with an 18/410 neck intended for finished preparations dispensed by pouring or tipping — oils, tinctures, tonics, serums and concentrates. As it is a solid screw cap without an opening, it is not designed for use with a dropper or spray applicator; closures with the appropriate mechanism are more suitable for drop-by-drop or spray dispensing.

Caps with the same neck type and ready-made packaging and cap combinations are available from Handymade. When combining your own packaging and cap, we recommend verifying the seal and behaviour with your specific formulation — especially with alcoholic and essential oil contents, which place greater demands on the seal.

Good to know

Before first use, wash and degrease the cap, or disinfect with isopropyl alcohol or ethanol and allow to dry thoroughly. Both the aluminium and the EPE insert can withstand repeated use as long as the insert remains intact and clean.

According to the technical documentation, the packaging material is suitable for contact with cosmetic products. With strongly solvent-based or concentrated essential oil contents, it is advisable to verify that prolonged contact does not affect the sealing insert.

Both the aluminium and the polyethylene insert are recyclable; where possible, separate the components before placing them in the recycling stream.

Frequently asked questions