>>6389674>>6389711>>6389728>>6389729>>6389730>>6390136>>6390160the turtles sewer back pack is a amphibious audio amplifier and it is a mechanical mechanism not electrical. just like the talking pull string dolls.
and on the strips you can see there is a small indentation on the left (the circle) when that part of the strip passes the sewer back pack (amphibious audio amplifier) it produces the sound. like the anon said you can also run it trough your fingernails and it will make a similar sound, but the turtles back pack amplifies it so you can hear it more better
