Tempered Glass Trivets

I am new to Temp-tations and am contemplating buying some of the bakeware. The only item I have purchased is the bread basket.

I am looking at the Temp-tations Old World 16-piece Oven-to-Table Set K27938. I like the idea of the Lid-It, and only wish there was a rectangular/square set that had lid-its for all the items. This set has tempered glass trivets. Does anyone use these trivets in the oven or are they not safe to be put in the oven?

Thanks!