More info about tape loops on my wiki:
My other standard tape loop design:
This tape design has been thought to have the tape loop doing a twist in the middle like a mobius strip. This allows you to double the time. *Note:* The part where the tape is reversed will sound muffled. The design of the tape is symmetrical, which allow the tape to be played in the two directions with no problem. Some guides are made to handle the twist of the tape properly. When doing the mobius twist, you will be able to return the tape to play it backward.

A version without the "twist" guide for a standard tape loop:

The tape length is ~420mm and length is a bit higher than 9 seconds or 18 seconds with the twist.
The author marked this model as their own original creation.