It was improved to be a better fit for Maker 3 Version and all machines with a roller bar in front; The calibration unit is now easier to insert and remove. Universal Design make more pens work with Cricut, not limited to the only brand Compatible with Cricut cutting machines compatible with Cricut Venture,Maker 4 3 and Maker,Explore Air 2Air,Explore 4 3 and ExploreNOT FOR ONE AND NOT FOR JOY Fit All Varieties of PensReplace the original pen adapter,and fit all pens with a shaft diameter less than 0.5 in,not for pencils and crayons.Work with infusible ink,ink,brush,fine liner,marker,oiled paint,detailing pen,gel,highlighter,glitter pens and much more pens Fits All Brands of PensCraverland pens adapter set is compatible with Sharpie,Bic,Crayola,Staedtler,Pilot,Sakura,Papermate,Pentel,Tombow and all kinds of brands of pensmarkers Easy InstallationRemove the original pen adapter.Insert the universal one with a quick calibration and a test; once youre proficient, pens will not need the depth calibration.Just take a look then you will know the required depth Easy to Store Small enough to organize in the device or in the organize box comes in this packet Set Includes2 x Pen adapters set,4 x calibration units,an instruction and a gift organize box Improved Version improved the calibration unit for easier use on Maker 3, making it fit for all machines whether the roller bar is in front Perfect Match color creamy white to match the machine, fits snugly in the pen clamp. Deviation May Exist due to the products versatility, there may be a little bit offcenter in the drawing that can fix with a test before running a project