Four blade or five? I have a perfect set of 15 7/8 X 29 five blade 15 degree unused since back from Bblades and a perfect set of 4 blades 17 X 31 checked by Bblades. $3000.00 for the fives shipped and 1900.00 for the fours shipped. I have changed my gear ratio so these no longer work for me. Doug 916 539-2540.