The two cartridge formats serve different filling processes. This comparison covers the practical differences buyers ask about most.
Both formats use a borosilicate glass barrel. The difference is what happens inside it, and that difference drives the filling line, the packaging and the pen configuration you will need.
Single-chamber cartridges
A single-chamber cartridge holds one formulation in one barrel. It is the simpler component: fewer parts, a more familiar filling process, and fewer ways for a fitment problem to appear. Our 3 ml single-chamber cartridge is supplied in clear borosilicate glass.
Dual-chamber cartridges
A dual-chamber cartridge holds two components separately within the same barrel, keeping them apart until the point of use. Our 4 ml dual-chamber cartridge is designed for this configuration, with component sets available for sterile packaging to match different filling processes.
What actually differs for the buyer
- Filling process: dual-chamber formats need a filling line and validation set up for two components.
- Pen configuration: a dual-chamber cartridge pairs with a pen built for that internal arrangement, such as our dual-chamber pen model.
- Packaging: dual-chamber cartridges are often supplied with separate component sets rather than as a single assembled unit.
- Volume: the formats are not directly interchangeable by volume, so the choice usually follows the formulation rather than the other way round.
- MOQ: the two formats carry different minimum order quantities, so confirm per format.
Choosing between them
If your formulation is a single component and your filling line is already qualified, the single-chamber cartridge is the straightforward choice. If the two components must remain separate until use, the dual-chamber format is the one to design around — and that decision should be made before the pen housing is chosen, not after.
Confirm fitment before ordering
Fitment between a cartridge, a pen body and a needle depends on the exact combination rather than the category. Send us your intended combination and we will confirm compatibility against the drawings.
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