Shimano EW-SD 50 Electric Wire, Black - OUT OF BOX Length:200mm It features built in cooling

It features built in cooling fins and cutouts for side visibility

a low battery indicator and like all Knog bike lights it is fully USB rechargeable

that’s advancement

Bar diameter: 31

Refilling & Replacing Options: Solid Refill Lid is ideal for adding powder

Shimano EW-SD 50 Electric Wire, Black - OUT OF BOX Length:200mm It features built in coolingShimano E Tube wires and connectors Frame grommets for E tube internal wiring compatible frames are sold separately, see Shimano Frame Grommet Kit Electronic Shifter Extra Parts Ultegra Di2 wires utilize Shimano's e tube technology; e tube is a two prong system and is NOT cross compatible with Dura Ace 7970 Di2 wiring All e tube wires may be used for internal or external applications