ROPP and aluminium cap questions, answered.

ROPP stands for roll-on pilfer-proof. It describes how the closure works: the cap leaves our works as a plain aluminium shell with no thread cut into it, and the capping head rolls the thread and the pilfer band onto the bottle's own neck during filling. Because the thread is formed against your glass, the seal matches that bottle exactly.

In Indian packaging, PP cap is short for pilfer-proof cap, and it refers to the same aluminium closure as a ROPP cap. It does not mean polypropylene here. You will also see it called an aluminium screw cap, a roll-on closure, a metal cap or an aluminium seal cap.

If a supplier quotes you for a plastic polypropylene cap when you asked for a PP cap, the wording has been read the other way — worth confirming before you order.

The lower part of the cap skirt is joined to the body by a line of thin bridges. When the cap is first twisted open, those bridges break and the band stays behind on the bottle neck. It cannot be reseated, so anyone handling the bottle can see at a glance that it has been opened. That visible evidence is what pharmaceutical, spirits and agro-chemical buyers are paying for.

We manufacture four sizes: 20 mm, 22 mm, 25 mm and 28 mm. Between them they cover the great majority of standard bottle necks in India.

The size refers to the bottle's neck diameter in millimetres, not the bottle's volume.

Aluminium alloy 8011, the grade used for pharmaceutical closures and foil. Sheet thickness is medical-grade, set by what the cap has to do: a heavier gauge where the neck finish is uneven or the capping head runs hard, a lighter one where cost per thousand matters more.

The wad is the thin liner pressed into the top of the cap. It is what actually seals the bottle — the aluminium shell only holds it in place.

EPE (expanded polyethylene) is our standard liner. It compresses evenly, suits most aqueous products, syrups, oils and chemicals, and keeps the bottle leak-proof and spill-proof through transport. Latex is a flowed-in liner that conforms closely to an uneven glass sealing surface, and we fit it where the neck finish varies or the product calls for it. If you are not sure, tell us what goes in the bottle and we will recommend one.

Yes. We offer dry-offset printing for a brand name, logo or tagline, and top embossing where you want the mark without ink. The flat cap top is a genuinely useful branding surface — on a shelf it is often the only part of the closure a customer sees.

Anodised silver and anodised gold are our stock finishes. Beyond that we colour coat to your approved specimen — blue, white, red, green or a matched shade. Colour is checked against the specimen and tested so that it does not leach in isopropyl alcohol over 24 hours.

Yes. We manufacture at Anakaputhur, Chennai and despatch across India — most regularly to Tamil Nadu, Karnataka, Telangana, Maharashtra, Gujarat and Delhi NCR, and anywhere else a transporter runs.

Yes, and we would rather you did. Send us your bottle, or tell us the neck-finish size and what the bottle holds, and we will send free samples with a quotation within two working days. Fitting the sample to your own capping head is the only test that settles it.

Aluminium ROPP and pilfer-proof caps fall under HSN 83099020. Our GSTIN is 33BMKPS1299A1Z1.

They are made to run on standard ROPP capping machines and sealing heads, manual or automatic. Because the thread is rolled on at your end, the head settings matter as much as the cap — which is why we send samples first and ask you to run them.