At STH we use affiliate links from programs such as Amazon.com and ebay to help pay for the site. As a result, some of our links do include our affiliate codes. These codes allow the larger sites to track whether someone makes a purchase at their site and attribute the referral to STH. We get a small fee for the referral. We do not accept free product from these vendors and do not endorse one vendor over another. Buy from whichever vendor you would like, but supporting STH is appreciated.