The lowest price component in this Turn Signal Lamp (model T : E22, E25) parts-list fiche is the Screw (4x30).
A sample from the products for the Turn Signal Lamp (model T : E22, E25) include: Bracket,rr Turnsignal Lamp,l, Lamp, Rear Turn Signal, Lead Wire, Relay Earth, Bulb(12v21w).
In this schematic the "Screw (4x30)" is used most often.