This is a COPY of the ORIGINAL.

Baby Lock Model BL402 Serger Service Manual - SEVENTEEN (17) pages.
Includes:

How to Remove the Exterior Parts
Positioning the Eccentric Cams
Lower Looper
Upper Looper

and more

Our manuals are printed copies, sized 8 1/2" × 11" and bound with a clear plastic front cover, a plastic comb spine so that they can lie flat when opened, and a cardstock back cover.
Most are enlarged from the originals.