Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Not necessary

This guide is simply not necessary. If you are installing your own Blum tandem drawer slides, then you already have all the tools necessary to accurately install the hardware. I can only see purchasing this if you're a professional and need to install 30 slides in a day.Blum's products are wonderful, but spend your money on a good square and collared drill bit set instead.