50pcs #14 x 1" Self Drilling Screws Roofing Screws with EPDM Washer Beakers and Test Tubes * Install Type: M8x13mm Threaded

* Install Type: M8x13mm Threaded Stem

Needle Diameter: 2mm / 0

tighten the screw at the proper position you need

Package Content:12pcs x Rubber Mount

5 piece Punch Needle

50pcs #14 x 1" Self Drilling Screws Roofing Screws with EPDM Washer Beakers and Test Tubes * Install Type: M8x13mm ThreadedDescription: 1. Material: Both the screw and the metal washer are made of carbon steel, a zinc plated surface finish, which is corrosion resistant; the black washer is made of EPDM, which is wear resistant and oxidation resistant. 2. Advantages: The hex washer head has a flange with an EPDM rubber washer on the bottom to prevent leaks, loosening and damage to mating surfaces. The underside of the hex head provides a large flat bearing surface that