I used to use Blackstone but the price seems to have gone through the roof. I ordered one of the Wix kits for about $20 on eBay. From what I understand the cost of the kit includes the analysis service. There were several addresses on labels inside so I sent it to the closest lab - ALS Tribology at 6180 Halle Dr. Suite D Valley View, Ohio. I sent it USPS Priority Mail and it was delivered on 02/17/2022. I haven't seen an e-mail from them so I'm not sure what's going on. I saved the slip with the reference number but it doesn't have a website listed to look up the sample. I tried the ALS Tribology site but I seem to need a business account to use it. Can anyone help? Thank you.