I have 1 set of older bi-flange tips and I can't remember where I got them. They work really well for me on my RHA MA750s. They are a bit shorter than normal bi-flanges and have a fairly large opening which actually helps the top end of these IEMs to my ears. I have attached a couple of pics and I am hoping someone will see them and let me know where I could order some more as back-ups. Thanks in advance for the help.