  Centimeter sized platelet single crystals of KFe2As2 were grown using a
self-flux method. An encapsulation technique using commercial stainless steel
container allowed the stable crystal growth lasting for more than 2 weeks.
Ternary K-Fe-As systems with various starting compositions were examined to
determine the optimal growth conditions. Employment of KAs flux led to the
growth of large single crystals with the typical size of as large as 15 mm x 10
mm x 0.4 mm. The grown crystals exhibit sharp superconducting transition at 3.4
K with the transition width 0.2 K, as well as the very large residual
resistivity ratio exceeding 450, evidencing the good sample quality.
