1.multi-function saw blade with double teeth saides and contacts 2. both alternative using. Instuction:1. description: multi-function saw blade with double teeth saides and contacts.2. material :Bi-metal.3.specification: 6" ,8" ,9" ,12".4.method: cutting metal , wood ,pipe and fiber etc.5.advantage: both saides can alternative using. multi-function saw blades