I don't know what company you might be talking about, but there's really no physical way to make "one piece, snap together" tracks for a VVSS (read: early'ish) Sherman due to their construction.
The closest you're going to get are the AFV Club or Panda plastic tracks. These are going to come with single piece tread blocks, and then separate end connectors. Some folks have used these without any adhesive, but I like to use a little MicroMark Liquid Mask to give them some adhesive, but remain flexible.
The AFV Club T-51s do show signs of a minor sink mark in the blocks, so extra clean up is needed. The Pandas should be perfect, but cost more.
Check out Terry's review:
The standard T-51 rubber block will assemble just like those.