The Femtolock™ 2 is a sub-100 fs jitter synchronization unit for Element™ 2 and Synergy™ ultrafast Ti:Sapphire oscillators. It allows locking of the round-trip frequency of oscillator pulses to a given reference RF-source. The use of multiple harmonics of the resonator round-trip frequency in combination with a simple and passively stable femtosecond laser resonator (based on Dispersive Mirror technology) enables low jitter levels.