Tubes look interchangeable in a catalogue. What separates them is invisible from the outside.

Decide the barrier from the formula, not the brand values

Mono-material polyethylene is recyclable and has a low barrier. EVOH or foil laminate has a high barrier and is hard to recycle.

Oxygen-sensitive actives and strong fragrances need the barrier. Stable lotions and cleansers do not. A recyclable tube that lets the product degrade is not the greener option once you count the returns.

Size the orifice against measured viscosity

Too wide and a thin product floods. Too narrow and a thick product will not come out, so it gets squeezed until the shoulder splits.

Ask your supplier to run your actual formula through the actual orifice before tooling. A datasheet viscosity is a starting point, not an answer.

Specify the tail seal for the format

The tail is the flat crimp at the end, made when the filled tube is heat sealed. It is where tubes leak.

A sample tube posted inside another order needs its own seal specification, not the setting used for a large body tube.

Keep artwork out of the seal zone

Anything printed where the seal jaws close gets crushed. Get the exclusion zone marked on the artwork template before design starts, not after the proof.

What to send when you ask for a quote

Formula type, viscosity or a physical sample, fill volume, quantity, and whether it needs an applicator. That is enough for a real quote and a sample.