The Renesas Electronics 551S series is a low cost, high-speed single input to four output clock buffer with best in class additive phase jitter of sub 50 fsec. The Renesas makes many non-PLL and PLL based low skew output devices as well as zero delay buffers to synchronize clocks.

Low additive phase jitter RMS of 50fs and extremely low skew outputs (50ps)
Low cost clock buffer and it has an input/output clock frequency up to 200MHz
Packaged in 8-SOIC, 8-TSSOP and 8-DFN