According to tests performed at the Alberta Research Centre in 2008, micro fiber roller refills hold more paint than standard refills and require fewer trips back to the tray. Four inches long, these micro-sized refills are made for primers, exterior paints and all latex and water-based coatings. Use them wherever a full-size roller isn’t ideal – doors, cupboards, window frames and tight spots. Fibers extend around the ends of refills to create smooth edges on painted zones. Top quality performance in a mini format.