The SN54F299 is obsolete and no longer supplied.
SN54F299, SN74F299 8BIT UNIVERSAL SHIFT/STORAGE REGISTERS WITH 3STATE OUTPUTS
SDFS071B - MARCH 1987 - REVISED APRIL 2004
D Four Modes of Opera
Original
Always verify details of parts you are evaluating, as these parts are offered as suggestions for what you are looking for and are not guaranteed.