FL-7161-1
USED TANENAKA TAKEX REFLECTIVE IMMERSION TUBING FL-7161-1 FL71611 S21830
A nice touch is that the model type is simply Various, leaving the choice up to you.
NEW TANENAKA TAKEX FL-7161-1 REFLECTIVE IMMERSION TUBING FL71611
What makes BSTFLEX worthwhile is the long lifespan you get from it.