I do not care, these wireless transceivers are the ideal solution for those who want to extend back and forth without having to repeat cables! Easily parameterable leave the finger on the receiver button for 20 or 30 sec and activate the transmitter. The reset does the same way but with a longer time, the red led flashes quickly. You can resume pairing! Perfect. Works with a battery but durable since short tensioning time. Bathroom completely redone so! The seller is fast, sending is correct in a box with a protection for the receivers all under soft plastic