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A short model helical undulator, 250 mm long, with a period of 14 mm was designed, fabricated and then subsequently tested in a liquid helium bath. The helical coil was wound with stabilized multi-filamentary MgB2 strand, 0.5 mm in diameter, in a wind and react mode with S-glass insulation followed by vacuum epoxy impregnation. Beam aperture of the coil was 7 mm, winding bore diameter 8 mm, coil winding OD=18 mm and the 1010 Fe pole (flange) has an OD=19.05 mm. The coil was measured for I c and magnetic field in the bore at 4.2 K in a liquid helium bath. The bore field as a function of depth was also determined near the critical current at 4.2 K. The load line of the coil was compared to short sample I c values.