Amazon.com : cysum CM520 Electric Mountain Bike, 29 Inch Electric Bike, 500W Men's Ebike, Electric Bicycle for Adults, 48V 14Ah Removable Li-Battery, One-Piece Rims, Shimano 7 Speed, Range of About 75km (Green) :
Shimano Disc Brakes | Worldwide Cyclery
Shimano Alivio BL-MT200/BR-MT200 Disc Brake and Lever - Longmont Bicycle Company & Front Range eBikes | Longmont, CO
Resin Disc Brake Pads compatible with Shimano Ultegra BR R8070 and BR RS805 | eBay