It is incomprehensible to me that there is no such parts with us in the drugstores. The to-find in our D-shaped gizmos I do not get along. The Y-shaped are the only viable. Do me a precaution equal ordered two packs on stock. That's what I'm going to have a long time, the parts are quite durable and wear resistant. The only drawback: The yarn is pretty thin and you have to be careful so as not to cut into the gums. There was a version from the same manufacturer which had taken a thread a ribbon. Unfortunately I could not find this type anywhere.
