This stereo contraption is completely waterproof.  It has flipped over on the river and been flipped back still playing.  The water that did get into the cool float was dumped out later at a more convenient time.  It has rollers on the bottoms and a dog leash to easily pull it down the gravel road/embankment or parking lot to the river (depending on where you go).  Although it does float, it has become a little lopsided due to a second battery being added for longer running time. A simple fix to this is to put the entire unit into a toob all on it's own, which makes it really difficult for it to turn over now.

The waterproof speaker on top was obtained at the local marine store.  It came as a pair but only one fit in the middle ridge of the lid so both left and right speakers wires were wired up to this one speaker. The speaker is secured the middle ridge of the lid with the installation brackets and screws.  Important to secure the screws with nuts on the underside of the lid.

The car stereo unit is inside a waterproof container obtained from the local marine store. The connections on the back(outside) of the waterproof container are siliconed to protect them from water.

The on/off switch is on the self-cut green plastic piece made from a plastic pot for a plant. It is a red on/off toggle switch.  The black you see around it is to waterproof the switch itself.  All connections for the switch underneath plus battery wires are all covered in silicone or black liquid electrical tape. I've tried the white liquid electrical tape but it was real runny, it may have been a different brand though, not sure at this point.  The good stuff will dry quick (10 minutes or less) and not be runny. Inside are two 12 volt batteries, wired in parallel. 

A small section of wire is stripped from positive and negative battery wires to allow for charging. The two batteries are closed cell 12 volt (18 amp hours and 7.2 amp hours). A marine charger is used. Once charging has completed, the alligator grips are removed from the wires and the bare strips are covered with the liquid electrical tape which can easily be removed later to charge again. The run time on the first battery was only 5 hours so we added a second battery. Some people like to make a long day of toobing.

The stereo is only used for mp3 discs as to avoid the hassle of mounting a radio antennae.  This is the big version of the Cool Float.  The stereo container and batteries are all extremely snug inside, if turned over while open, they are snug enough to where they won't drop down on their own.  If you make one, be sure to take measurements to get the right battery sizes.  Both batteries are not the same size.  If the top battery had been the same size, the stereo container would not open properly and there may not have been enough room for the on/off switch plate.

Industrial Strength Velcro (with sticky back) is used to hold the lid secure. Velcro is also used to secure the plastic switch plate to the batteries.  This was all put together last year and worked great!  This year the Velcro is beginning to become unstuck so superglue may have to keep it lasting for a long time.  By the way, finding materials that will stick to the different plastics used in coolers has become an adventure in itself.  If superglue won't work on this one, I'll just replace the Velcro with some new Velcro.

The black you see around the edge of the Cool Float is black liquid electrical tape. The first couple of trips on the river proved that they are not manufactured to very high standards and water did get inside.  Silicone and/or liquid electrical tape to the rescue (once we let all the water inside the float drip out.)

The wheels are made from a big trash can wheels.  They are held onto the contraption by use of giant, intertwined, plastic zip cords. Here is where the dog leash is attached. This allows us to yank hard on it to get it over big steps.  We do have to be careful though as the second battery did make the unit a little top heavy so it will roll over under the right conditions during pulling. If we had put the dog leash on the float itself, it would have put undue stress onto the manufacturing seal which we've already had issues with, no need to chance that again.

Zip cords are wrapped around the bottom wheels and around the Cool Float itself. Additional zip cords are added to ensure that the wheel cords do not slip off.

As you can see in the photos, it has become lopsided, mainly from the extra battery and the additional small coolers for drinks. Normally there are two more small coolers to help even out the weight or a separate cooler is used altogether for the refreshments.

A remote control can be used for volume and song advancement.  No picture is available but it has been wrapped up in clear packaging tape and then all but the very top was covered in more liquid electrical tape to seal it up nice and tight.   We also have Velcro on the inside to secure the lid to hang on the side while we manually go in to mess with the controls if need be. (Just being sure not to let water drip onto the stereo)