... White area on the top of the cap. Jiui® 50ml conical-bottom centrifuge tube Special selected high-clarity polypropylene assures the ... , chemical resistibility and obdurability. Smooth, flat surface polypropylene caps for conical bottom tubes. The universal design make the tubes are suitable ... /ctnr Ray50pcs/bag,500pcs/ctnr Ray25pcs/rack, 500pcs/ctn 50ml conical-bottom centrifuge tube