$13.96 (List $20.99, -30% -5% Coupon) 9" Edger Blade (Ryobi 638006008 compatable)
After giving up on finding a true Ryobi replacing (e.g. need a 9", can only find their 8") I started using the knock-offs from China. I honestly can’t tell the difference. I always replace when they get worn enough to be unbalanced.