Unlike the old sergers, these revolutionary tubes used to carry the thread cannot be blocked under normal sewing conditions. As the machine is stitching, the threads are travelling through the same threading tubes. This prevents a build-up of lint and fluff, which prevents thread entanglement and helps ensure that your machine stays relatively clean.
That's it! No longer do you need to worry about guides and tangled threads. Change any thread without re-threading the rest, thread the entire machine in under one minute, and thread in any order!