The component with the lowest price in the OPTIONAL PARTS SWITCH PANEL - RIGGING ACCESSORIES schematic is the Ybs67-5 Washer, Spring.
In this schematic the "Screw(6k0)" is used most often.
A sample from the products for the Optional Parts Switch Panel - Rigging Accessories include: 0/m Key (466), O/m Key (113), Bolt (661), Panel, Switch.