I see a lot of questions on how to make your own ecaller popping up as usual during this time before most people start hunting snows for the spring. Who wouldn't like to have a crisp sounding, portable, last all day ecaller that doesn't break the bank. I certainly do, in fact I like having 3-4 of them. So here is my part list on how to NOT spend an ridiculous amount ($300-$500) on a commercially made ecaller and virtually make 2-3 for the exact same price. (Note; may be able to find parts cheaper elsewhere) The housing- 12.99 http://www.academy.com/webapp/wcs/s...10151_10051_12502_-1?ICID=CRT:0145-00028-0140 The amp- $18.90 http://www.amazon.com/Pyle-PLMPA35-Channel-Amplifier-3-5mm/dp/B004HJ931M The Speakers- (2 to 4 depending on your preference)- $45.80-$91.80 http://www.amazon.com/Pyle-PHSP4-6-...TF8&qid=1423002206&sr=1-1&keywords=power+horn MP3 Cable to Amp- $2.53 http://www.amazon.com/Cables-Unlimi...ie=UTF8&qid=1361389178&sr=1-3&keywords=3.5+mm 12 Volt Rechargeable Battery-(1 or 2 will run ecaller all day) $17.99 (Note: I use a piece of wood to seperate this battery from the amp so that it sits tightly and doesn't have to be removed for charging. ) http://www.amazon.com/Volt-Recharge...sr=8-10&keywords=12+volt+battery+rechargeable Now your going to need 1 duplex 120v outlet, with faceplate. On these you need to break the copper connection that sits in between the screws so that your channels from the amp are separated. NOT doing this will lead to overheating of amp. These will have to be inserted into the casing but using a saws all to make a hole big enough for the outlet to set with the faceplate covering it. One channel of the amp goes to one part of the outlet, and the other channel goes to the remaining. You will need 1-2 Male 120v plugs. I say 1-2 because you can connect 2 speakers to 1 plug, just pre-twist the wire together before you put it inside said plug. If you want to have each speaker have an individual plug you will need outlet extensions. I recommend NOT doing this. Misc Wires for connects, and its always a good idea to have an extra fuse for amp. If needed I can provide pictures of completed product, but with a little intuition you will bang out an ecaller in virtually no time. Total Cost with 1 batteries, 4 speakers and misc parts(roughly)- $157 + shipping of parts. Adding a remote is at your discretion, I personally haven't found the need for them, but adding one is simple and easy and will add anywhere from $10-$25 per unit. Good luck, and remember "Save the tundra"