MODEL Thirty 3G Twenty 3G 20XLc 15XLc QFRXCc QFRSolo/c Active 28-30dB 24-26dB 22-24dB 16-18dB 10-12dB Passive Only Passive 12-22dB 12-22dB 12-22dB 12-20dB 24-26dB 28.7dB Battery Hours 2 AA/ 30 hrs 2 AA/ 40 hrs 2 AA/ 50 hrs 2 AA/ 50 hrs 2 AA/ 25 hrs N/A Auto Shut-Off Yes Yes Yes Yes Yes N/A PST EQ Yes Yes No No No N/A Weight 16 oz 16 oz 15 oz 15 oz 14 oz 11 oz Cell Phone Interface Yes Yes Yes Yes Yes Yes Music Interface Yes Yes Yes Yes Yes No Warranty 5 years 5 years 3 years 3 years 3 years 3 years