After tossing many good machine needles because I had no idea what size they were I made myself know what needle I am using in my machine. I write down the size and type of needle when I change it and write the date and time too. I have started using Organ Titanium coated topstitch needles so when the other brands I have are used up, keeping track won't be hard, the needles are colored coated so I can see at a glance what they are.