Not sure on the difference between the p66 vs standard garmin dual 50/200 besides p66 is 600 vs 500 watts. Garmin says the UHD models are not compatible with P66, going to call and get clarity as my ice unit is a 73cv UHD and would save money to put the transducer on that vs a new additional finder. Also for $80 might worth trying the dual frequency garmin transducer, not sure how much detail you would need for the wide cone purposes.