Amazon offers DEWALT Oscillating Tool Blade for Grout Removal, Fast Cutting, Carbide (DWA4220) for $15.75 . Eligible for free super saver shipping.

Product Description:
The DEWALT DWA4220 Oscillating Fastcut Carbide Grout Removal Blade is designed with UNIVERSAL FITMENT for use on all major brands of oscillating tools (no adapter required). This is ideal for easy grout removal. The Sign wave design provides 2X faster grout removal than the Fein 6 35 02 128 01.

• UNIVERSAL FITMENT for use on all major brands
• No adapter required
• Sign wave design provides 2X faster grout removal