We report the design and performance of a single frequency all-fiber distributed feedback (DFB) laser sources employing fiber Bragg gratings (FBGs) emitting in the 2-<inline-formula><tex-math notation="LaTeX">\mu</tex-math></inline-formula>m region. Output powers up to 65 mW CW and optical signal-to-noise ratios of <inline-formula><tex-math notation="LaTeX">></tex-math></inline-formula>65 dB/0.05 nm are obtained. The emission wavelength of the DFB-FBG laser can be fine-tuned with picometer accuracy over a range of 0.6 nm by controlling the pump power and laser temperature. The single frequency source is amplified with polarization-maintaining Ho- or Tm-doped fiber amplifiers to an output power of 1 W CW at 2051 nm or 0.7 W CW at 2039 nm. Heterodyne measurements yield instantaneous laser linewidths of 5 kHz FWHM for both native and amplified signals.