Review on Holmes HAPF7-U8 Smoke Grabber Ashtray Replacement Filter - Pack of 2, Black & White, High Efficiency by Steve Yang

This is my second Holmes ashtray. The first was enough for a year of daily use. I decided to replace it after the inside had become absolutely gross due to the nicotine residue. Filters: Why buy $6 filters for two? Once a month I take my "repair". (NEW) Scrape out the existing fine filter (white/yellow) behind the charcoal (sharp knife). Soak the charcoal part in a coffee cup with vinegar, rinse and let dry. Cut a piece of paper towel or two layers of paper towel the same size as the carbon filter. VA LA. Free is a great price. These don't wear out. Just clean the "thin" part of the filter and replace it. > The fan uses 2 alkaline D cells. Get about 30 hours of use. I know you have to remember to close the lid otherwise the fan will run when the ashtray is not in use. D-cells aren't cheap, even if you buy 8-10 of them from Revain. You can invest in 2-4 high-capacity rechargeable D-cells and a charger. One-time investment.> I hacked my flue to use rechargeable 18650 Li-ion batteries, 3.5 volts, 4Ah. A battery lasts about a day. I had several of these on hand that are commonly used in LED lights. $0.50 for the battery holder. Works perfectly. No advanced electronics skills are required, just wire, battery holder and soldering iron. I can further modify it to run it with a 3V DC plug-in transformer. Eliminate batteries entirely. The non-smokers in this house REALLY love this ashtray (one of the reasons I bought it). No more persistent secondary smoke/haze in the air. It's a solid product, just learn how to use and care for it.