I found this out the hard way when I launched one into orbit accidentally trying to reprogram my "here is" code.
I got to thinking, "Surely I can use an o-ring for this."
mykin.com sells o-rings. So I ordered 50 of them. Standard AS528-016. 1/16" x 5/8" made of silicon.
Then installled them on the answer back drum.
Of course, nothing is as simple as it seems.
First time, I had the tabs facing the wrong way so they missed the contact levers.Then I had the code wrong. Third time's a charm. My "here is" reads 76470 jeff tx now.
Bending a small J-hook in a paper clip made inserting the tabs very easy. Lift the o-ring up out of the way, insert tab and let the o-ring back down.
And here is an easier version of the chart to read.Answer Back Coding.pdf
Hope this helps.
Jeff