42TPI (35-550). TPI=Teeth Per Inch.
Fine Kerf Razor Saw has a blade with .010in. kerf, 6-1/2in. length, 1-3/16in. depth, and steel back for stability.
For pull stroke cuts in balsa, other wood, plastic, copper and brass. Leaves smooth edges.
Blade is NOT Interchangeable or Replaceable.