The 490mm,19.3 blade size is (560mm x 54mm x 7mm) or (22.1" x 2 1/4" x 5/16") with 7 holes, hole spacing is 75mm or 2 61/64 to hole center, hole diameter is 6mm for 6mm bolt.
Blade Protective Carrier or Sheath is for storage or sending blade for sharpening
7 Stainless Steel Bolts and Washers for replacement of low carbon Chinese bolts that stretch and create a lose blade