It also doesn't ship world wide, even to Canada I made an order, with no way to see what shipping was and got an email saying they only ship to commercial or schools. That's a terrible e-commerce experience. Sites like NCIX were way better than this.
10+ years ago they used to ship to individuals in Canada, but I vaguely remember some negative word-of-mouth discussions about them when individuals got burned by "customs fees" which was actually companies like UPS ripping off people by charging unreasonable fees to do customs clearance paperwork. Mcmaster probably didn't want to deal with that.
If they do think you're a business (maybe this means someone at your business has ordered before), they will not only ship to you but instantly let you use net-30 payment terms automatically. I had one experience of ordering some parts to a university in Japan when I was a student, and the parts were shipped the same day, along with an invoice. I didn't even have to create a login. [0]
[0] I wouldn't be surprised if this is no longer true due to know-your-customer legislation.
I'll accept the downvotes and say it's not a universal problem. Upon more research it seems if you do not send a Referrer header, McMaster inserts a history entry using the history API. I can make it work/fail by tweaking network.http.referer.XOriginPolicy. It's interesting that McMaster is the only site I use in 2022 that has a problem with it.
Not sure what's going on. I can reproduce in Firefox with DDG and Google.
Edit: it only happens for me in Firefox with particularly locked down settings. It turns out McMaster is not actually inserting a 3XX redirect, it is happening via the history API.
As I updated elsewhere: upon more research it seems if you do not send a Referrer header, McMaster inserts a history entry using the history API. I can make it work/fail by tweaking Firefox network.http.referer.XOriginPolicy. It's interesting that McMaster is the only site I use in 2022 that has a problem with it.
What search term did you use? I just tried "mcmaster 4-40 screw", clicked on the first link, clicked on the back button, and was back at the Google SERP.