Sundown Audio U Series 18" v.2 Dual 4 ohm 1750 watt RMS Subwoofer Car Audio

Black Aluminum 3” voice coil former for superior heat dissipation High Temperature Round-Wire CCAW voice coil with high-temp black adhesive Double stitched surround Heavy duty cast basket Spring loaded terminals accept up to 8 gauge Stitched-on double-XL tinsel leads Rear vented pole piece Rear drilled gap-venting Innovative high-velocity cast aluminum vented frame spacer ring Magnet ID shorting ring Top-Plate Cooling Channels Cast Aluminum surround bolt-on rings Optimized for small ported or bandpass enclosures   U-18 T/S SPECS U 18" D2 U 18" D4 RE (Ohms) 3.8 6.1 FS (Hz) 31.3 31.4 VAS (L) 135.4 135.4 Qes 0.37 0.42 Qms 3.41 3.55 Qts 0.33 0.38 Le (mH) 2.62 3.97 BL (NA) 29.9 35.3 Mms (Grams) 444.1 441.3 Cms (uM/N) 0.06 0.06 Sens (dB @ 1w/1m) 92.3db 91.8db