This gasket has a little ridge or a lip.made to lastCompatible with 600W / 900W Extractor blades and Flat milling bladesThese gaskets are meant for those NutriBullet blender with a lip Will not fit NutriBullet blenders where the gasket doesn't have a lip.These Gasket Replacements for NutriBullet 600W 900W blenders fit on either NutriBullet Extractor Blade or NutriBullet Flat Milling Blade, or any of the lids.for NutriBulletBlenders Replacement PartLip for Nutribullet Blenderfor Nutribullet BlenderReplacement Partscolour:grayMaterial:plasticsize:Outside diameter :4 inchesInside diameter :3.75 inchesPackage Contents:4 *DURABLE gray gasketPlease note: NOT COMPATIBLE with Nutri Ninja, NutriBullet RX, Magic Bullet or Baby Bullet blenders.Only the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.