The white polypropylene ribbed unlined caps are available in a variety of sizes ranging from 13/415 to 120/400. The white plastic caps are ribbed for a better grip when twisting the cap on and off, and feature a matte finish with a slight ridge on top of the closure. SKS offers a wide variety of container options that are compatible with these plastic caps. Match the cap code of the white plastic unlined caps with our selection of containers for proper compatibility. As always, be sure to test all cap and container options with your products for proper compatibility.