McMaster-Carr Cross-Reference
Look up a McMaster part number and find candidate equivalent listings at other suppliers. McMaster's price isn't shown, since you already know it.
McMaster is blocking the server for this part
Open the part on McMaster and click the bookmarklet below. It reads the page in your own browser, where McMaster doesn't block you, and sends the specs here with no server involved.
Drag this link to your bookmarks bar once. On any McMaster part page, click it to send that part's specs here.
Install the bookmarklet (works for every part, no server needed)
Drag this link to your bookmarks bar. On any McMaster part page, click it to send that part's specs here, which works even when the server lookup above doesn't.
Paste specs / manual entry (use if the lookup and bookmarklet both fail)
Supplier links
Supplier pages open in your browser; they block servers, so the match is yours to judge. (Your browser may ask to allow pop-ups for "Open all".)