Don't risk your bearing popping out of place or making a mess. The flange presses against the housing wall, so vibration and other sudden forces parallel to the shaft (thrust loads) won't knock these bearings off-kilter. Made of naturally slippery plastic, there's no lubricant to maintain. No lubricant means no oil that could drip off, wash out, or collect dust, so they're ideal for spic-and-span spaces. They stand up to thorough cleanings since they won't rust or warp from moisture.