Specification Brand : uxcell BulletPoint : Price For: Each System of Measurement: Inch Head Type: Knurled Item: Thumb Screw Rockwell Hardness: B68 to B71 Tensile Strength: 57, 000 Class: 2A Thread Size: 1/4-20 Material: Steel Length: 3/4" Finish: Black Oxide Head Height: 1/2" Head Dia.: 5/8" Country of Origin (subject to change): United States BulletPoint1 : Product Name: Knurled Thumb Screw; Package Content: 15pcs x Knurled Thumb Screw; Main Color: Silver Blue BulletPoint2 : Material: Carbon Steel, Zinc Plated; Weight: 60g BulletPoint3 : Knurled Head Diameter: 11mm / 0.43"; Head Style: Round Knurled Head BulletPoint4 : Thread Size: M3 x 30mm / 0.12" x 1.18" (D*L); Thread Pitch: 0.5mm BulletPoint5 : Total Length: 32.7mm / 1.29"; Thread Style: Fully Thread Color : silver DriveSystem : None ExteriorFinish : Zinc ExternallyAssignedProductIdentifier : 7440105270053 ItemName : uxcell M3x30mm Thread Zinc Plated Knurled Round Head Thumb Screws Silver Blue 15pcs ItemPackageDimensions_Height : 12.6 centimeters ItemPackageDimensions_Length : 1.3 centimeters ItemPackageDimensions_Width : 9.5 centimeters ItemPackageQuantity : 1 ItemTypeKeyword : thumb-screws Manufacturer : uxcell Material : Carbon Steel, Zinc Plated MeasurementSystem : Metric MetalType : Stainless Steel MetalType1 : Zinc MetalType2 : Carbon Steel ModelNumber : Z2126 NumberOfItems : 1 PartNumber : a17082500ux0003 ProductDescription : Description:Knurled head provides extra grip for manual tightening. Usually found on thumb screws, a knurled surface on the head gives a better gripping surface, making it easier to tighten or loosen fasteners manually. Thumb screws are designed to be tightened and loosened by hand. Tools not necessary for tightening or loosening. Knurled Thumb Screws are installed with your fingers and are used to hold light covers in place and other ornamental products.