Plastic cap, 24/410, disc top, black

A disc top cap opens by pressing one side of the disc: the opposite side lifts up and reveals the dispensing opening. The bottle can thus be opened and closed with one hand, and the cap remains screwed onto the neck at all times. It is particularly suitable for shampoos, shower gels, liquid soaps, conditioners, and body lotions – products that are dispensed in portions directly into the palm.

The cap is made of polypropylene (PP) and is suitable for contact with cosmetic products including surfactants, oils, and emulsions. The black colour is opaque and neutral, so it can be combined with clear, amber, and coloured bottles. The cap is designed for bottles with a 24/410 neck.

How a disc top dispenses

The cap does not dispense the product by itself – it only opens and closes the small opening. The amount dispensed is therefore controlled by squeezing the bottle or tilting it.

• One-hand opening – a single press of the thumb on one side of the disc is enough, which is practical in the shower or with wet hands.
• Small dispensing opening – the product comes out in a narrow stream, so no more is poured out than needed.
• Closure with no loose parts – the disc is an integral part of the cap; nothing gets set aside or lost.
• Flat top – a closed bottle can be stored upside down when the product is running low, provided its shape and stability allow it.

What products it suits

A disc top is suitable for liquid to medium-viscosity products that can flow through the small opening:

• Hair care – shampoos, conditioners, and liquid masks dispensed into the palm.
• Shower gels and liquid soaps – the closure can be operated with a wet hand and closes again with a single press after use.
• Body lotions and light emulsions – provided they are fluid enough to be squeezed out of the bottle.
• Massage and body oils – the narrow opening slows the flow so the oil dispenses in drops or a thin stream.
• Water-based products – micellar waters and tonics poured onto a cotton pad.

The 24/410 neck and bottle selection

The designation 24/410 describes the thread: the first number is the neck diameter in millimetres, and the second defines the thread type and height. The cap fits bottles with the same neck designation, which is listed in the specifications of each bottle. Bottles with a 24/410 neck and ready-made bottle-and-closure combinations are available from Handymade.

With a neck of the same diameter but a different second number, the cap may not seat and seal correctly. When using a custom combination, it is therefore recommended to verify the seal, dispensing behaviour, and compatibility of the packaging with the specific formulation.

What is good to know before filling

Preparing the cap. Before first use, the cap is washed, disinfected with isopropyl alcohol or ethanol, and left to dry completely. Special attention should be paid to the space under the disc and the dispensing opening, where water takes longest to evaporate. Boiling is not recommended, as high temperatures may affect the shape and seal of the plastic closure.

Filling the bottle. The bottle should be filled to the nominal volume, not to the brim. The nominal volume is the capacity the bottle is designed for under normal filling conditions. The total brim-full volume is the physical capacity up to the neck. The difference between the two provides clearance for the closure and for expansion of the contents with temperature changes. When a bottle is overfilled, the product is pushed into the thread and around the opening when the cap is applied.

Frequently asked questions