 MityMeg Plus
MityMeg Plus 
It works well, lighter than the old voice coil megaphones we had which kept cutting out. 
The 
"detachable" microphone is the only microphone, and is not  detachable completely - it clips on the back where the mike is on a  regular megaphone for normal use, but you can detach it from there if  you're in a fixed location and want to put the megaphone down and use  the handheld microphone. There is not a separate built-in microphone on  the back, and you cannot completely detach the one microphone. 
The battery level feature is good, but inconvenient - instead of  being in back where you see it every time you use the megaphone it's on  the side so you have to remember to look at it while pressing down the  talk button. 
The switch between off and the two sound effects is a simple slide  switch, it would be better if it were momentary for the sound effects so  you have to hold it one way or the other to get the sound effects,  right now you have to slide it to the sound effect and then slide it  back. 
But overall it works well, sound is clear, and it has nice features  like Velcro to keep the batteries locked down in the battery holder.
 25-Watt MityMeg Megaphone
This is a great megaphone all the way around
 25-Watt MityMeg Megaphone
This is a great megaphone all the way around. The ceramic  pick-ups/amplifiers make the unit lightweight and give it a battery life  many times longer than the older magnet pick-up style megaphones. I  don't know why all megaphones being made now don't have this technology  -- the high end magnet-style units cost the same amount and often more. 
There are three other features that I really like about this megaphone that other smaller and slightly cheaper ones don't have. 
First, it has a trigger on/of switch at the top of the handle,  
making it perfect for one-handed use. It does have whistle and siren  features if you need them, but they are accessed independently of the  on-off trigger switch. (I really like that) 
Second, it has an easily adjustable dial volume switch on the back  that can be toggled with the thumb of the same hand using the megaphone  -- also perfect for one-handed use. 
Third, it has an internal gain adjustment dial. This is ideal for  performance and recording, because it allows a little variation in  distortion. Just be careful not to adjust the gain to high if you're  going to be talking loudly into it or, naturally, you'll get feedback. 
Other nice features: 
-Battery strength indicator LED lights which show Low, Mid, and Hi. 
-Removable rubber cone protector that keeps the end of the bell from being scuffed when set down.
The 25W megaphone has every feature I was looking for: internal  microphone, trigger on/off talk switch, adjustable gain, volume  thumb-toggle dial, long battery life, lightweight, and above all,  excellent sound quality. I'm an actor/musician, and I purchased the S602  megaphone for performance use and it fits my needs perfectly. I've even  used it for crowd control while filming a scene with lots of extras.
~Testimonials Courtesy of Amazon reviews. 
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