MOTORS - Check your Specialized motor spindle type. These carbon eCranks are made for Specialized eBikes with "ISIS" spindle motors.
MAIN BOLT - The eCranks with ISIS Spline use M24 alloy Main bolt/Self extractor.
Q- All eBike motors have different width spindles and this directly affects the Qfactor when the crank is installed. These are the Qfactors when you install this crank on these motors :