Specification Brand : ZIUZI BulletPoint1 : Specification: These knob head diameter is 1.57 inch / 40 mm and height is 0.59 inch / 15mm, T track knob threading fits for 5/16"-18 rod. BulletPoint2 : Material: Made of high quality nylon and galvanized carbon steel, smooth surface, high strength, good toughness and strong anti-aging ability. The thru knobs are threaded to a bolt to clamp them together for a long service life. BulletPoint3 : Easy to use: Star-shaped nut design, with deep threads and accord to ergonomic, can be very stable tightening screws. The bolt can go all the way through the tightening knob, which is handy when the screw happens to be longer than you need it to be. BulletPoint4 : Wide Application: Star Knobs usually used for lathe machine, mechanical equipment, drill press, fixture, fences, saw fence etc. where 5/16"-18 thread nuts are needed. BulletPoint5 : You will get: 6 pcs 5/16-18 thread black clamping knob nuts, well-made and comfortable hand grip, non-slip without scratching hands. These wing nuts require little effort to loosen and tighten. Color : Black DriveSystem : Star ExteriorFinish : Stainless Steel FinishType : Polished IncludedComponents1 : Knob IncludedComponents2 : Screw ItemName : ZIUZI 5/16-18 Thread Knob Nut, 6 Pack 5/16 Star Shape Hand Tighten Clamping Knobs Black Screw-On Nuts ItemPackageDimensions_Height : 0.5 inches ItemPackageDimensions_Length : 3.9 inches ItemPackageDimensions_Width : 5.9 inches ItemPackageQuantity : 1 ItemShape : Hexagonal ItemTypeKeyword : star-knobs Manufacturer : ZIUZI Material : Nylon Material1 : Plastic Material2 : Iron Material3 : Metal Material4 : Alloy Steel MetalType : Brass MetalType1 : Iron MetalType2 : Brass ModelNumber : a24022200ux0508 NumberOfBoxes : 1 NumberOfItems : 6 PartNumber : THREAD-KNOB-516-18-6PCS ProductDescription : ZIUZI 5/16-18 Thread Star Shape Screw-ON Hand Clamping Knob Nut