High-quality Chip The anti-interference chip can effectively shield noise and restore good sound quality, providing you with better sound and smoother performance. Powerful Signal Reception Equipped with four freely retractable antennas for stronger signal reception. Effective operating distance up to 80 meters (260 feet) in open space. Actively Tracking Frequency Receiver will actively track the frequency, even if the long distance can also be stable connection. Switchable Frequency Each transmitter has 16 frequency points for you to adjust. You can switch frequencies at will to avoid interference from nearby signal frequencies. You Can Use It For What Will You Get 4 Handheld Wireless Receiver*1 Handheld Microphone*4 6.5mm Audio Cable*1 Power Supply*1 Anti-slip Ring*4, Manual*1 2 Handheld & 2 Bodypack Receiver*1, Handheld Microphone*2 Bodypack*2 &Lavalier Microphone*2 &Headset Microphone*2 Audio Cable*1, Power Supply*1 Anti-slip Ring*2, Manual*1 4 Bodypack Wireless Receiver*1, Bodypack *4 Lavalier Microphone*4 Headset Microphone*4 6.5mm Audio Cable*1 Power Supply*1, Manual*1 4 Gooseneck Wireless Receiver*1 Gooseneck *4 6.5mm Audio Cable*1 Foam Microphone Windscreen*4 Power Supply*1, Manual*1 Comparison of Wireless Microphone Systems DU4004 and D-440 4 Bodypack Add to Cart 2 Handheld & 2 Bodypack Add to Cart 4 Handheld Add to Cart 4 Gooseneck Add to Cart 4 Handheld Add to Cart 4 Bodypack Add to Cart 2 Handheld & 2 Bodypack Add to Cart Customer Reviews 4.6 out of 5 stars 15 4.6 out of 5 stars 15 4.6 out of 5 stars 15 4.6 out of 5 stars 15 4.4 out of 5 stars 12 4.4 out of 5 stars 12 4.4 out of 5 stars 12 Price $149.89$149.89 $149.89$149.89 $149.89$149.89 $149.89$149.89 $169.89$169.89 $135.20$135.20 $135.20$135.20 Product Model DU4004 DU4004 DU4004 DU4004 D-440 D-440 D-440 Number of Channel 4 4 4 4 4 4 4 Adjustable Channel 4*16 4*16 4*16 4*16 Fixed frequency Fixed frequency Fixed frequency Type Lavalier/Headset Handheld/Lavalier/Headset Handheld Gooseneck Handheld Lavalier/Headset Handheld/Lavalier/Headset Power Source Battery Powered Battery Powered Battery Powered Battery Powered Battery Powered Battery Powered Battery Powered Connectivity Technology XLR XLR XLR XLR XLR XLR XLR