SET OF 4 WHEELS. See other listing for individual wheels. Yamaha Timpani Third Wheel (Part W6541000) replica. Yamaha has stopped production of these third wheel attachments. These are ones I am building and selling as a replacement for lost or broken wheels. I will try and keep a steady stock of these, so shoot me a message if you are in need of more than is currently available. Contact me if you need to purchase for a tax exempt organization.