|Range||U+FFF0 - U+FFFF|
Specials is a short Unicode block allocated at the very end of the Basic Multilingual Plane, at U+FFF0–FFFF. Of these 16 code points, five are assigned as of Unicode 11.0:
U+FFF9 INTERLINEAR ANNOTATION ANCHOR, marks start of annotated text
U+FFFA INTERLINEAR ANNOTATION SEPARATOR, marks start of annotating character(s)
U+FFFB INTERLINEAR ANNOTATION TERMINATOR, marks end of annotation block
U+FFFC ￼ OBJECT REPLACEMENT CHARACTER, placeholder in the text for another unspecified object, for example in a compound document.
U+FFFD � REPLACEMENT CHARACTER used to replace an unknown, unrecognized or unrepresentable character
U+FFFE <noncharacter-FFFE> not a character.
U+FFFF <noncharacter-FFFF> not a character.FFFE and FFFF are not unassigned in the usual sense, but guaranteed not to be a Unicode character at all.