Dropouts Bicycle Frame Building Parts: Aluminum Dropouts Material: 6061-T6 Aluminum Surface treatment: Black Anodizing, Silver Anodizing and Raw The Bicycle Aluminum Dropouts in Morong we made are in Aluminum by CNC Machining in tight tolerance and excellent appearance. Some are made by die forging+CNC machining which can help you saving cost if you have proper quantity. If you need the bicycle...