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We have lased the new material, LiSrAIF 6 :Cr h (CrH:LiSAF). The single crystals were grown by the horizontal zone melting technique. The spectroscopic properties of Cr + :LiSAF are similar to those of other 10w~field Cr H -doped systems, although the emission cross section is strongly 11' polarized and is also somewhat larger than has been measured for other fluoride hosts. The free~running lasing wavelength of Cr H :USAF is 825 nm, and the tuning range extends from at least 780 to 920 nm. Using Kr laser pumping, we obtained slope efficiencies of 36% and 14% by utilizing output couplings of 4.8% and 0.8%, respectively. On the basis of these results, the extrapolated maximum efficiency of 53% is determined, to be compared to the quantum defect-iimited value of 78%. It is concluded that a moderate level of excited state absorption (ESA) loss is responsible for the reduced efficiency of the Cr 3 +:LiSAF system. This contrasts with the related results previously obtained for LiCaAIF 6:Cr3 +, where it was concluded that the effects ofESA were negligible [IEEE J. Quantum Electron. QE-24, 2243 (l988)J. 1051