The Free On-line Dictionary of Computing (30 December 2018):

Commodore 1570

    Commodore Business Machines's allegedly "advanced"
   disk drive for use with the C128.  It is basically a 1541
   with the capability to use "burst loading" (like the
   Commodore 1571), and lots of new bugs.

   The Commodore 1571 was a double-sided version of the 1570.

   (1996-04-07)