Kasablanka corporation manufactures various types of laboratory plastic products. This is an iso 9001-2000 certified company. Press caps are part of those products. Kasablanka`s press type caps are of two types which fit a different variety of plant culture bottles. Smaller ones are for test tubes [25mm x 150mm]; bigger ones are for jam bottles [500gms-kc/059]. These caps are translucent autoclavable & reusable. The unique design facilitates excellent light penetration & is easy to use.