Transistor Pad Description:  Size: 19mm x 13mm x 0.3mm Hole size: 3mm Color: Light Blue  Washer Description:  Hole size: 3mm for M3 Screw  Diameter: 6mm  Color: Beige  Height: 2.7mm  High Temperature plastic  Usage is to isolate electrically transistor or other components from the Screw mount  It is 100% Electrical Insulator