WHY the Van Alstine Design is Superior! The Van Alstine S-100 sipes faster, easier, and with more control than ever imaginable. Whether cutting simple sipes or creating complex siping patterns, the possibilities are unlimited. Cutting open sipes with our #1 siping blade allows an extremely thin strip of rubber to be removed, adding even more flexibility to the S-100 Siper. As an added bonus, the S-100 easily cuts small grooves, making this tool not only the perfect siper, but also an inexpensive but effective groover.