Clear Plastic Cap, Ribbed, 24/410

The plastic cap 24/410 with a ribbed surface is a screw closure for bottles and small bottles with a 24/410 neck finish. It provides a simple and tight seal wherever the contents do not need to be dispensed with a dropper, pump, or sprayer – during filling, transport, and storage of finished products, semi-finished goods, or raw materials. The transparent design does not alter the appearance of the bottle; the overall impression is determined by the container and label itself.

The cap is made of polypropylene (PP) and has an inner EPE liner, i.e. expanded polyethylene foam. When tightened, the liner presses against the rim of the neck and seals the joint, so the closure holds even thin liquids that might seep through the thread alone – tonics, hydrolats, oils, serums, or alcohol tinctures. The ribbed circumference makes opening and tightening easier, even with wet or greasy hands.

Key features

• 24/410 thread – one of the most common neck sizes for cosmetic bottles; the cap fits both glass and plastic containers with the same neck type.
• EPE liner – the soft foam layer compensates for minor unevenness on the neck rim and reduces leakage and evaporation of the contents.
• Ribbed surface – improves grip when opening and closing, which is particularly useful with oils or when wearing gloves.
• Transparent polypropylene – a lightweight, shatter-resistant material that tolerates aqueous, oil-based, and alcohol-based formulations.
• Cosmetic grade – the material is suitable for direct contact with cosmetic products; a declaration of conformity is available with the product.

Which bottles and contents it is suitable for

The cap is designed for bottles and small bottles with a 24/410 neck finish, which you will find in the Handymade range also as ready-made container + closure combinations. With a custom combination, we recommend verifying the seal with the specific formulation, as the height and shape of the neck rim vary slightly between bottles.

In terms of contents, it is a universal neutral closure: aqueous preparations (tonics, hydrolats, facial waters), oil-based preparations (body and massage oils, oil serums), and alcohol-based solutions (tinctures, alcohol bases before fitting a sprayer). It is also suitable for temporarily sealing a bottle during production – for example, while an emulsion cools down and before transferring it to the final container with a pump.

Good to know

Preparation before first filling. Wash both the cap and the bottle, disinfect with isopropyl alcohol or ethanol, and allow to dry completely. Do not soak the EPE liner for extended periods – a brief wipe with alcohol that evaporates quickly is sufficient.

Filling to the nominal volume. Fill the bottle to the nominal volume stated on the container, not to the brim. The nominal volume is the quantity for which the bottle is designed for standard filling; the total brim-full volume is the physical capacity up to the neck. The difference between them is a margin for the closure and for the expansion of the contents with temperature changes. In an overfilled bottle, the liquid reaches the liner and is squeezed out through the thread when tightened.

Tightening. A moderate, firm hand pressure is sufficient. Excessive tightening permanently compresses the liner and reduces its sealing performance in subsequent use.

Heat and pressure. Do not fill with hot contents. As the contents cool, a vacuum forms inside the closed bottle, which deforms thin-walled plastic containers and makes opening difficult. The cap is also not intended for contents that release gas, such as fermenting extracts.

Essential oils and solvents. With prolonged contact with concentrated essential oils or solvents, the foam liner may swell slightly. For such contents, we recommend verifying the closure's behaviour on a single sample over several weeks.

Repeated use. After washing and disinfecting, the cap can be reused as long as the liner retains its shape and is neither deformed nor stained. Both PP and the polyethylene liner are among commonly recycled plastics.

Frequently asked questions