The RC-EL3 is the remote manufacturers model of the remote, where the rc506 is what is found in the menu and its roku's model number of the remote. Later remotes may have different discrete app buttons and so the RC506 will change to different model number. But the number in the battery compartment will still have the rc-eL3. Give them both, RC-EL3 & RC506. I have four of those combination remotes.
Edmund
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