3 pin DMX Loop End Terminator Plug - 120 ohm resistor  

This 3-pin DMX Loop End Terminator is compatible with all 3-pin DMX devices and cables. Use this device to terminate a DMX line so that you don't get signal bounce backs occurring in the line. 

In general, a DMX line should always be terminated. Terminate your DMX line when you are using many DMX fixtures on a single line. If the line is not terminated correctly, you can get what is known as a "shadow signal" bouncing back down the line. The longer the cable run, the more the risk of "shadow signal" occurring. 

A 120 Ohms resistor across pins 2 and 3 simulates to the transmitting DMX device that the line is infinite in length, therefore the signal does not reflect back down the line.