Yes, the hearing aid zinc-air cells are inexpensive and the tip on covering most of the air holes is a good one-- but I am lazy, and I like things to fit just right. So I bought some MR9 adapters. 2 from CRIS (expensive! Excellent fit/function) and I just ordered a couple of less expensive ones on eBay, they haven't arrived yet. I had Gossen repair/calibrate my old LunaPro and they sold me the PX14 for $80US, so the 34 pound one looks like quite the bargain to me. I have so many devices that use the mercury cell that it's worth it to me.