Profile: Knobs Direct Inc. is a source for industrial plastic knobs and handles. Our product line includes ball knobs, knurled knobs, bar knobs, three arm knobs, four arm knobs, seven arm knobs and small grip handles. Our wide selection of ball knobs include phenolic or rubber materials in diameter sizes, including 3/4", 1", 1-1/4", 1-3/8", 1-3/4", 1-1/2" and 2". We offer a selection of neoprene soft grip ball knobs. We supply knurled knobs with internal and external threads.