Over the years I have frequently used magnetic drain bolts in my vehicles. This was particularly true back in the day for my motorcycles, as the oil filtering systems were not nearly as good back then as they are today. There are differing schools of thought as to whether or not magnetic drain bolts are effective, but I tend to view them as an inexpensive extra layer of protection for my engines.
When I bought my CB1100EX, I asked the dealer if Honda offered a magnetic drain bolt for it, and of course the answer was "no". Consequently the parts guy consulted an aftermarket catalog, and ordered me a drain bolt. The drain bolt size for our CBs is 14mm - 1.5 x 16. Anyway, the aftermarket drain bolt made in Taiwan, came in and I paid around $10 for it. The first oil change came later, and I went to install the drain bolt after removing the stock drain bolt and draining the oil. As I started to screw the new magnetic drain bolt in by hand, I felt it bind, and immediately removed it ( yes I had cleaned the pan threads first ). My thread gauge showed 1.5 thread, but aparantly the thread was just slightly off. I was not going to risk damaging the thread in the oil pan, and it was long past being able to get a refund, so the Taiwan bolt was pitched in the trash. If I had a 14mm - 1.5 die I would have tried running the bolt through it, but my largest die was 12mm - 1.5.
I started doing some research on magnetic drain bolts after that episode. I found that most of what is available out there is made in China, Taiwan, or Hong Kong. Nope not going there again. I also found that many of the aftermarket bolts are made of aluminum. No thanks there also. I did find a couple of premium magnetic bolts though, Dimple, and Gold Plug. Dimple touted very strong magnets, but I did find a couple of drawbacks, a price of $35 plus shipping, and some reviews that indicated breakage due to thin bolt side walls, the result of accommodating large O.D. magnets.
What I ended up going with is Gold Plug,
https://goldplug.com/ . The model for our CBs is MP02. The bolts are machined from stainless steel, cost $18.95 plus economy shipping, and include a new aluminum crush washer. The hex head takes a 17mm wrench, and the magnet is strong. I was/am so impressed with this company and the quality of their drain bolt, I bought one for my Monkey Z125, and both of our cars. The bolts are machined by Gold Plug, in Montana. Anyone that likes old school magnetic drain bolts, and the corrosion resistance of stainless, will like Gold Plug. [attachment=10860]