In our experience from using many different types of windscreen repair systems over the last 30 years is that non-UV resistant syringes are repeatedly used for approximately 20+ applications. Eventually residue from all the previous applications blocks the chamber from repeated natural UV exposure or the rubber piston seal within the chamber becomes perished or unattached. 2020 Technology windscreen repair tools use windscreen repair resin application which does not expose windscreen resins to natural UV as part of the repair process.
Between applications the single use syringe and needle are not IPA cleaned as would be recommended meaning that each application of fresh and pristine resin mixes repeatedly with residue from previous resin doses which have been left in the chamber exposed to air and UV from previous dosing applications. Contamination of old windscreen repair resin in the chamber with new windscreen repair resin is not a good starting point for any windscreen repair system.
With GT Smart windscreen repair kits you do not need the commonly used NON UV Resistant plastic syringes adopted by plastic windscreen repair DIY kits. GT Smart windscreen repair kits protect the UV unstable windscreen repair resin in its UV resistant bottle and needle to enable it to be used in pristine condition at the point of use.