Double end stud with nibs on flange

This knurled head bolt consists of a series of small ridges that are rolled onto the surface of the head, provides a better grip, making it easier to turn the bolt by hand without the need for tools.

This screw features a rectangular head with a cup-shaped top.

a.) A double-ended threaded rod is a type of fastener that features threading on both ends of the rod, with a section in the middle that may or may not be threaded.

b.) This design allows the rod to be used in applications where two components need to be joined, often with nuts or other fasteners securing the ends.

a) 壓鑄螺釘(螺絲)，也稱為自鉚螺釘, 是用於鈑金製造和其他需要牢固, 永久緊固的應用的緊固件. 它們通常由頸部或頭底下帶有滾花或鋸齒狀的螺紋螺柱搭配平面頭型或法蘭頭型組成。

b) 安裝過程包括將壓鑄螺釘插入金屬板上已預先沖孔/鑽孔的孔中. 然後, 使用壓力機或類似工具, 將螺釘的滾花部分壓縮到周圍的金屬中, 從而形成牢固且永久的連接, 無需焊接或額外的硬體. 其優點具有高強度、抗振動和薄型安裝等。

T-foot mounts are commonly used in solar panel installations primarily on pitched or sloped roofs. It is designed to be used with wood screws and can be quickly installed on the roof.