BOX Three Prime 9 Speed Twin Lever Shifter - Black - Single Shift - 22.2mm Bar Clamp - 9 Speed YGroup_7033697239085 so you can choose to

so you can choose to pair them up with your favourite chamois or a protective base layer if you wish

or reinstallation of ISIS Drive and Shimano Octalink thread in bottom brackets

Cons: Probably not quite powerful enough for night time trail riding

sportive comfort padding and a flat rear section to allow freedom of movement

The S1 is an economy package that has a fixed resistance mode

BOX Three Prime 9 Speed Twin Lever Shifter - Black - Single Shift - 22.2mm Bar Clamp - 9 Speed YGroup_7033697239085 so you can choose toBox shook up the market when they introduced their wide range, 11 50T 9 speed drivetrain. The Box Three is the value option within the Prime 9 lineup. With Prime 9 you still get the wide range offered on competing 12 speed setups but with fewer shifts required to go up and down the gear range. Spend more time riding and less time tinkering with your gears on a Box Prime 9 setup. Who's this item for: Any rider wanting an 11 50T range in a 9 speed