Elevator bolts feature a wide, countersunk flat head and a shallow conical bearing surface. The square neck under the head locks the bolt into place. Also known as belt bolts, elevator bolts are commonly used in conveyor systems. 18-8 stainless steel is functionally interchangeable with type 304 stainless steel. Stainless steel significantly improves resistance to tarnishing or corrosion.DIMENSIONAL ATTRIBUTES Diameter (Nominal): 5/16" Thread Pitch: 18 Diameter (Dimension): 0.3125" Diameter (Minimum): 0.298" Diameter (Maximum): 0.324" Length (Nominal): 2-1/4" Thread Length (Nominal): 0.875" Neck Width: 0.342" Neck Height: 0.25" Head Diameter (Minimum): 1.188" Head Diameter (Maximum): 1.227" Head Height, Overall (Minimum): 0.094" Head Height, Overall (Maximum): 0.114"PRODUCT ATTRIBUTES Category: Elevator Bolts System of Measurement: Inch Brand: Aspen Fasteners Head Style: Flat Head Head Style Detail: Square Neck Thread Length: Standard Thread Length Thread Direction: Right-Hand Thread Material: Stainless Steel Material Grade: 18-8 Stainless Steel Coating: Uncoated Origin: Origin Undefined Standards and Specifications: ASME B18.5