Both the 45° and the 60° blades are made from high grade carbide steel rods and are polished to razor sharp perfection for precise cutting.  Both blades are compatible with the Siser Blader Holder and they easily click into place thanks to the housings inner magnet.  With the 45° angle, the perfect amount of blade is exposed for almost all projects and materials, including: vinyl, cardstock and other lightweight materials.  If you need an all-purpose blade that can accomplish most projects, then the 45° blade is for you!  The increased angle of the 60° blade makes slicing through thicker materials like Brick 600 HTV and Craft Felt easier than ever.  If you're cutting specialty materials with increased thickness, then you'll want to keep the 60° Blade locked and loaded.