This Premium Select 4 Piece Trim Roller Set, includes two 4 inch White/Knit Fabric Roller Covers, a 4 inch Roller Frame & Plastic Paint Tray. The high density white knit fabric on these roller covers make them ideal for use with the new thicker Paint + Primer paints on the market today. The increased density of the fibers provides excellent paint pickup for more coverage between loadings and fewer trips to the paint tray. The 100% polypropylene core with patented thermo-bond technology not only seals the fibers to the core to keep them from releasing into the paint but also holds up under hours of use and can be cleaned again and again for re-use. Engineered for use with all paints and stains including oil and latex, these rollers perform to ensure a high-end look on flat and eggshell finishes in small spaces where a 9 inch roller simply won't fit.