Leaf Blowers

I just purchased a 125BVx blower vac. I noticed at home that on the box it said you can extend the standard 2 year warranty to 3 or 4 years. This required the purchase the Husqvarna premix fuel or 2 stroke oil. See Husqvarna.com for details. I have search the site and cannot find the details for extending the warranty. I did purchase the premix fuel with the blower. Any help as to where I can find this information will be appreciated.