If you pay for your oil samples in advance, you’ll get a discount per sample. After you place your order, we will send you however many kits you need. When you send in a sample, just mark the oil slip as “This is one of my prepaid samples.”
Remember that the kits are always free. We track the number of credits you have on file – it doesn’t matter if you send the oil in our kit or not. It’s possible to end up with more (or fewer) kits than you have credits for. If you have questions, call us at 260-744-2380 and we’re happy to tell you how many credits you have left.
Want to add TBN or TAN tests to your bulk order? You can do that here: https://www.blackstone-labs.com/product/tbn-tan-soot-test/