These are 6x3/4" Button Head Sheet Metal Screws by Du-Bro.

Features

Zinc plated metal construction with clear chromate.
Non-slip socket drive insert.
The large head of the screw acts as a washer.
A new design that's great for mounting servos, cowls, landing
gear, etc.

Includes

(8) Screws

Specifications

Length: 3/4"
Diameter: 6mm

Comments

This uses a 5/64" size allen wrench (DUBR1162)