Shimano Dura Ace BR-7700 Bicycle Brake Calipers Retro Road Bike Brakes Brand: Shimano. Primary Group: Dura Ace 7700. Model: BR-7700. Colour: Silver. Type: Caliper. Design Category: Dual Pivot. Quick Release: Yes. Cable Attachment Bolt: 5mm Allen Key. Attachment Bolt Type: Recessed Allen Key. Reach Category: Short Reach. Min Reach: 39 mm. Max Reach: 49 mm. Weight: 305 grams. Country: Japan.