This object is a "MF20 1024K MOS STORAGE" module from a KL10. It is an extra deep 6 high DEC format multilayer (probably 4) PCB. It has front and rear stiffeners. It includes a 10 by 16 array of Hitachi HM4864P-2 chips.
Manufacturer
Digital Equipment Corporation (DEC)
Place Manufactured
Singapore
Identifying Numbers
Model number
M8570
Printed on barcode sticker on bottom of board stiffener
Model number
M8570
Etched near front edge of circuit side of board
Model number
M8570 AH
Stamped in red on front of board stiffener
Other number
5016346-01 B1
Etched near front edge of circuit side of board
Other number
ZG43400272
Printed on barcode sticker near front edge of component side of board