Since a few of you have complained about amazon being referral links in other threads:

http://www.amazon.com/gp/product/B004GZZGWC/ref=oh_o00_s00_i00_details

For example, the "ref=oh_o00_s00_i00_details" part, is NOT a referral link. It is a part of the url indicating what part of their website you were linked here from, such as their promotional emails or your shipped orders.

None of these give anyone any gains, other then showing other people sales/things off amazon.

If someone is referraling you, it wouldn't have ref= at the end and would likely be based off of clicks on their website.