Engineers wear thick white spacesuits with large black ribbed collars. The stem may also be ribbed or fluted in shape. The compartments are then ribbed and paneled. Such designs include corrugated slabs and ribbed slabs. Calyx tubular, toothed, usually ribbed below teeth. The outer surface of the receptacle is ribbed or wrinkled. Some varieties are ribbed and faintly warted on the outer surface. The sides are ribbed with the centre either flat or having winged protrusions. Plants produce fruit which is ribbed spindle-shaped. Tile may be ribbed to accept a plaster finish, or smooth. The surfaces of the nutlets can be slightly ribbed, smooth or warty. The barrel radiators were made of ribbed cast aluminum. Those socks are usually ribbed at the top of the ankles. Some are designed to look like penises, while some are ribbed or wavy. The undersides of the arches are ribbed for reinforcement.