PitbullAudio has been selling the Logitech UE900S Ultimate Ears noise isolating IEM for $159.99 at ebay.com again. It is the lowest price ever so far and it is different link from yesterday's link (Yesterday's deal has ended).
Input Sensitivity: 101.2 dB @ 1 kHz, 50mW
Frequency Response: 20 Hz - 20 kHz
Noise Isolation: -26 decibels of ambient stage noise.
Impedance: 30 Ohms @ 1 kHz
Internal Speaker Configuration: 4 proprietary balanced armatures with a 3-way crossover
Input connector: 1/8" headphone jack into any personal monitoring system.
Warranty: 1 year.