When you want to buy a ton of bolts, you can post a message on an RFQ service to have suppliers send you competitive bids. To find the bolt you want, the menus are not well-designed. Maybe they try to have all the right information, but it's not easy to use. When I finally narrowed down my choice to a particular bolt, they only provided the name of one supplier. The purpose of this site seems to be to comparison shopping for industrial supplies, but I did not see evidence of actually having more than one supplier listed.
Suppliers pay to bid for buyers' contact information.
Operating since 1996. A big site. Ads don't get in the way. All kinds of industrial supplies, but You have to give your email address to get any information. A search engine for all kinds of industrial supplies, not just fasteners.