I have my Labrador Retriever lady bought the green collar and am absolutely happy with it! It has already done us good service. It lights up really bright, well I think you can choose between two different flashing intervals and continuous light. A small criticism I have: I find the LED ribbon inside a little too short, that the collar could be quietly lit 10cm longer. It is probably due to the closure to be extra shorter, so that the LED strip is not nipped in the closure. Maybe my dog also has a thick neck to ;-). If a line is applied to the collar, the collar so lights only down. In addition, the collar is easy to maintain and easy to clean.