The kit was recommended by Banwy who say they use the single tube kit for fixing spoilers. For my T5 I used Sticks like sh*t to fix a GRP barn door spoiler, no primers just stuck it on, stayed on for five years. Looking at YouTube, I have seen the primer applied to the bodywork and the glass activator applied to the glass. I applied the primer to the both the bodywork and the spoiler and all seems good so far.