This is a replacement straight crankarm (no offset) that is the same as what is shipped with the BBS01 & BBS02 drive units. You must specify a side L or R when ordering. The Right is the drive side and the Left is the non-drive side. You must use the right side crankarm for the correct side of the bike

Be aware when mounting pedals that the left side pedal is reverse threaded so you tighten it backwards (counterclockwise)..Drive side is normal, clockwise to install it