Second generation Pentium II. Adds a 100MHz FSB. Came in 350MHz, 400MHz, and 450MHz. There was also a 266MHz version with a 66MHz FSB. In August of 1998 Intel started to lock the clock multipliers on these babies to prevent overclocking.

I own a 400MHz Deschutes. it's one of the early ones, and its clock is not locked.