We haven't had to do much repair on someone else's LED signs, but right now we are servicing a "Supercuts" sign that we did not build and we know it's Sloans LED's and power sources, but we can not determine what generation they are and they built the sign! - called the company we are doing the work for and they do not know what generation they are either.With all of the different types of LEDS and different gernerations out there it is hard for a smaller company to keep it all in stock. we normally order product as we need it or have our customer send it to us.