We　report　self-starting　femtosecond　operation　of　a　127-MHz　SESAM　mode　locked　Cr:ZnSe　laser　around　2420　nm.　A　thulium　doped　double　clad　fiber　laser　at　1908　nm　was　used　as　the　pumping　source.　In　the　normal　dispersion　regime,　stable　pulse　pairs　with　constant　phase　differences　in　the　multipulse　regime　were　observed.　The　maximum　output　power　was　342　mW　with　respect　to　incident　pump　power　of　4.8　W　and　the　corresponding　slope　efficiency　was　10.4%.　By　inserting　a　piece　of　sapphire　plate,　dispersion　compensation　was　achieved　and　the　intra-cavity　dispersion　was　moved　to　the　anomalous　regime.　A　maximum　output　power　of　403　mW　was　obtained　and　the　corresponding　slope　efficiency　was　12.2%.　Pulse　width　was　measured　to　be　408　fs　by　a　collinear　autocorrelator　using　two-photon　absorption　in　an　InGaAs　photodiode.　The　laser　spectrum　in　multipulse　operation　showed　a　clear　periodic　modulation.