This property defines the Unicodes which belongs to Arabic Extended B block
Characters like ࡰ,ࡱ,ࡲ, etc. are listed under Arabic Extended B Block.
43 Characters are present in Arabic Extended B Block starting with the Unicode point U+0870 that represents the character ࡰ.
Currently, as per latest version 15.0.0, Unicode supports 328 number of Block. Here are a few examples - Latin Extended E,Adlam,Aegean Numbers, etc.