When you’re setting up your Dura-Ace Di2 disc brake bike and want to buy the shifters with the matching disc brake calipers, the Shimano Dura-Ace Di2 ST-R9170 Shifter/Hydraulic lever with Assembled BR-9170 Disc Brake is the ticket.
This has both the slim, almost impossible to tell it’s not a rim brake lever, lever, the brake fluid reservoir, and the shifter, in one ergonomically- and aesthetically-pleasing package, and the matching BR-9170 Flat Mount Disc Brake calipers, front and rear.
Levers weigh 360g for the set. Calipers weigh 515g for the set. Set also comes with hydraulic hoses and Shimano mineral oil brake fluid. Shift components, including wires, must be purchased separately.