The black plastic screw cap is one of the most common and practical closures in the cosmetic and essential oil segment: simple, reliable and clean-looking — its contrasting black top surface looks attractive on amber glass. This 156-piece pack of 20 ml bottles is ideal for those seeking a cost-efficient, well-proven closure for everyday formulation work.
What this 156-piece pack contains
156 amber 20 ml glass dropper bottles + 156 black plastic screw caps. The bottles are approximately 75 mm tall with a 30 mm diameter and an empty unit weight of around 30 g. The total package weight is approximately 0.78 kg. The neck uses a standard GL18 thread.
Amber glass and UV protection
Amber glass is one of the best storage solutions for sensitive essential oils, botanical extracts and cosmetic preparations. It filters out the shorter wavelengths of visible light and most of the UV spectrum, thereby slowing photocatalytic oxidation. Amber glass is neutral and does not release substances into the contents.
Black plastic cap details
The cap is a simple screw-style polypropylene closure with a standard internal liner for a leak-proof seal. It is not a tamper-evident (security-ring) design — it is specifically a simple screw cap. The clean black appearance creates an aesthetic contrast with the amber glass, making it well suited to private-label products. Being a plastic cap, very strong concentrated essential oils (particularly citrus or spice monoterpenes) may have a slight long-term effect on it; however, under average use, durability is adequate.
Areas of use
- Bottling of essential oil blends and aromatherapy synergies
- Storage of skincare oils and face serums
- Hydrosols and light cosmetic liquids
- Everyday bottling of private-label products
- Sample bottles for demonstrations and gifting
Cleaning and reuse
Wash the bottle in warm soapy water, rinse with alcohol to remove scent residue. Do not place the plastic cap in the dishwasher due to high temperatures — hand washing is recommended. Glass and plastic are each recyclable when separated; before recycling the cap, rinse and dry it.