VOB 11 Low Profile Spec Sheet / VOBs / By Eckel Noise Control Technologies Performance OCTAVE BAND FREQUENCY (HZ) 125 250 500 1K 2K 4K NIC NOISE REDUCTION (dB) VOB-11 LP 19 28 38 46 52 54 40 Optional Features Door Window (Laminated) 9” x 45” (229mm x 1143mm)