pvc cap of a pen 1.100% silicone 2.different color and design 3. green material,non-toxicm,odorless 4.so 1,100% eco-friendly silicone raw material, heat-resisting, cold-resisting,soft and good feeling-touch.2,It non-toxic ,non-slip,non stick and harmless to body.3.diferent colors and sizes is available.4.Aging-resistant,Ozone-resistant,acid/alkali resistant, voltage resistant insulating,wearable, ...