The industry standard.  Recommended to me by my music teacher.  (Made the novice mistake of first ordering a less expensive voice pickup mic.  Not happy with the results.)  I used for amplifying acoustic mandolin and pennywhistle flute in conjunction with Marshall guitar amp.  Had a hum/buzz problem which was not a  grounding loop.  Turned out to be a shielding problem with the mic.  Drove me nuts at first but solved by adding and Audix T-50K inline impedance matching transformer and a Planet Waves XLR male to 1/4" female balanced adapter (available thru Amazon) in the circuit.  Everything now working great.