The short answer
Confirm dip-tube length and end configuration with the pump supplier using the actual bottle interior, pump assembly and product formula. Avoid selecting length from the external bottle height alone.
The visible bottle height includes features that are not available liquid depth. Base thickness, internal geometry and the pump’s fitted position affect the usable space for the tube.
Use the assembled geometry
Provide the bottle drawing and physical samples to the pump supplier. Ask how tube length is measured for the chosen assembly. Review the tube’s position at the base and its interaction with the internal shape.
Evaluate product use
Assess priming, spray delivery and residual contents using the intended formula and agreed test method. Check representative component variation rather than approving only one hand-assembled sample.
Procurement checklist
- Use the actual bottle and pump combination.
- Confirm the tube measurement convention.
- Review internal base geometry.
- Trial priming and delivery performance.
- Record approved length and end configuration.
Common question
Will the longest possible tube always improve product use?
No. Tube position and shape can interfere with function. Select the configuration through supplier review and representative use tests rather than maximizing length.