Dual Battery Parallel connector

This connector is amazing and definitely solved my problem. No more more stopping to unscrew and disconnect and reconnect. This was a major issue for me when it rained. I most of the time didn't even bother bringing my second battery on these days. My ebike has its controller and connections inside the downtube. The black box itself is really small so I was able to place it right inside where water makes no contact. I can choose which battery I want to use first or just use them both at the same time all without ever having to disconnect. Amazing product well worth it. 48v 26ah + 48v 21ah .

You are someone who really cares. Thanks for your time.

Works well and pretty much as advertised, but I have one small issue of having to flip the power rocker on the second connected battery a few times to make sure the controller picks it up. If I don't do this or forget to, I will end up riding with one battery and don't notice until half way through when I have half the charge I expect. Other than that it works well and gives me about 80-100 Miles range mostly electric with my two 19.2Ah batteries, which is actually about 10-15 Miles more than draining one, then switching and draining the other. Better performance and less overall stress on each battery.

This is a must have! It makes any bike more practical. It allows me to use my stock battery with any battery I can afford at the moment. The adapter is easy to use and made exceptionally well.

Using two 48v batteries one 10ah and one 14ah. One is high quality LG cells, the other generic from China. Both batteries have BMS limit of 20amps. Device works well, can leave everything hooked up, can charge each battery with separate chargers while all hooked up. Device has stayed cool to the touch while riding.

Perfect. I use my bike to commute to work and appreciate a little assurance I will get there and back with battery charge left. Very easy to install to add a second battery.

If one does real hills, this thing helps reduce dreaded voltage sag on the big/long ones. I regularly do one ~50 mile loop where the display on my Rad with stock OEM controller and single active battery dropped 2 bars during climbs in three different places, but no more after adding this thing and a 17.5 Ah battery alongside the original Rad OEM 14 Ah one (13S9P now!). You DON"T get that benefit if you manually switch/swap batteries one at a time. Don't let some flatlander nincompoop tell you that if your bike drops 2 bars there's something wrong with it just because they can't pull ~750 Watts for more than the 6 seconds it takes to get to the 20 MPH limiter cutout (unless they ride with the brakes on or in quicksand). I suppose it's now time to start worrying about battery/controller/motor/wiring/connector thermal overload or cutout instead of voltage sag on those 2+ minute ~750 Watt climbs, it's always something... I tried two other parallel battery adapters before this one, both of which were cheaper and had smaller 3D printed plastic cases with NO heatsink. They both failed within 100 miles. I'm at 1000+ miles and counting on this one so far with zero problems/glitches! I do centuries on my bikes so reliability is especially important when a long way from home. Even so, it's best to carefully plan plug and wiring configuration when installing any component like this so it can be easily removed/bypassed if necessary or when troubleshooting.