The 5170 Accessory Kit is included with the purchase of the 550 Walk-behind scraper.  This kit can also be purchased separately and includes the following items:

147: 4" x 6" blade

6285: 3" x 6" heavy-duty blade

6265-BD: 3" x 8" self-scoring blade

7050-202: 3" x 10" premium high-tempered blade