... .any size for silicon O ring 2.Non-toxic,Waterproof,Dustproof 3Under high wear and pressure ... 4.OME welcom silicon O ring Features:1) AS-568, PG standard and non-standard Silicone ... O-rings 2) Various colors available, such as black, green, yellow, blue, red 2) RoHS ,SGS,FDA,LFGB directive compliant green ...