Merriway BH02531 (4 Pcs) Whitworth Slotted Round Head Machine Screws with Nuts, 3/16 inch x 1 inch Bright Zinc Plated - Pack of 4 Pieces : Amazon.co.uk: DIY & Tools
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Astro Essentials 1/4" Socket Head UNC Bolts (x2) 3/4" Long | First Light Optics