This is an automotive/marine caulk that can be used for temporary glue on boot application of up to 2 weeks.
See our blog articles on gluing on boots with Sikaflex here: https://timberlinetack.com/blogs/news/scoot-skins-glue-on-hoof-boots-using-sikaflex-227
Sikaflex has also been used to repair boots. We have not used them for this purpose ourselves but here is a video by a boot user: https://youtu.be/AsEhCj6RYRI
Apply in a well ventilated area wearing a mask. Official full cure time is 9 days but we glue on boots the night before using. Follow blog instructions carefully.