Why do I see white material floating in the syringe? (t:slim X2 insulin pump)

The material is likely a very small piece of white cartridge septum that was cut out by the syringe needle and drawn into the syringe. 


The chance that the cartridge septum material can be dispensed back out of the syringe and into the cartridge is small. 

The white septum material is chemically inactive and biocompatible. It is okay to still use the syringe even if white septum material is observed. If the material were to make it into the cartridge and then move out of the insulin reservoir, through the valve components and into the infusion set tubing, an occlusion would occur and the pump would alarm. 

We recommend using the syringes and needle tips that come with your t:slim X2 cartridges. If you believe your cartridge box is missing the included syringes or needle tips, check for them underneath the inside flap of the cartridge box. 

Make sure you are using proper load technique. If you have persistent issues with using the syringes or needles that come with your t:slim X2 cartridges, please contact Customer Technical Support. 

Load a Cartridge Quick Reference Guide (PDF) > 


Load Sequence Tips (t:slim X2 insulin pump): 

  • Do not re-use or re-fill cartridges. 
  • Use the syringe that came with your cartridges. 
  • Use room-temperature insulin. 
  • Ensure there are no visible cracks in the cartridge. 
  • Ensure that there are no visible air bubbles in the syringe. 
  • We recommend filling the syringe with a minimum of 120 units. 
  • Only used approved insulins 
  • Ensure you insert the needle in the center of the white cartridge fill port. 
  • Do not overfill cartridges. The base of the syringe’s plunger should not pass the 3mL line. 


  • Ensure you remove the residual air from the cartridge before filling. 




Was this article helpful?
11 out of 11 found this helpful
Return to top