It’s important to ensure profiles are clean before installing the insert!
This photo is a classic example of what can happen if the profiles aren’t clean before installing the insert.
Tredsafe's adhesive tape is high spec but like most tapes, it is not capable of adhering through grease, grime, dust or debris.
If the profiles are not clean the insert will not have a good surface to adhere to and overtime the insert will move, leaving a gap at one end and overhang at the other.
More often than not there are numerous contractors onsite trampling over freshly fixed nosings. Therefore, it is important to clean the profiles using isopropyl alcohol (or similar) before installing the insert. This will ensure the best possible adhesion and will not only increase the lifetime of the product, but will provide your new stairs with a safe and aesthetically pleasing result.
Once nosings are fully installed, read here https://tredsafe.co.nz/assets/default-site/Insert-Maintenance-and-Cleaning-Guide-PDF.pdf to learn about how to clean and maintain stair nosings.