These bodypack transmitters are great - durable (we use ours 4-5 times a week), convenient (uses AA batteries - cheap/a lot) and simple (no manual ones Frequency sync with IR sync; Sensitivity booster is on the side). The only very minor issue is that the antenna is very flexible and I wish it was stiffer - it just looks ugly upside down. I can understand why (I don't want him poking you in the side). In my experience, real world battery usage is about 4 hours non-stop on AA alkaline batteries, the base station is about 100 feet away from you and the gain is set to very low.
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