Small speakers that are used for MP3 players. make sure they are battery operated.. Attached to a Walkman Cassette or CD player you now have a spare wildlife cassette or CD players.
Tool boxes with a radio and MP3 speaker system in them..Same as above..Attach an Cassette player, CD player or a MP3 with wildlife sounds and you have a wildlife caller...
Look on all the racks at Bonton, Kohl's etc...They always have a battery powered speaker system for people to attach their MP3 players, cassettes, CD players etc..Again attach the appropriate cassette player, CD player or mp3 with wildlife sounds and you have one heck of a wildlife caller..
Remember best to get all of these speaker system that require the speaker to use AA or AAA batteries.. The power of the speaker system makes all of these things outstanding calling outfits. How many of these do I own?....several........
Best yet after Christmas... Kohl, Bonton, almost give these things away... Don't forget look at all the electronics in Ross Department Store too..