This property defines the Unicodes which belongs to Kanbun block
Characters like ㆐,㆑,㆒, etc. are listed under Kanbun Block.
16 Characters are present in Kanbun Block starting with the Unicode point U+3190 that represents the character ㆐.
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.