This property defines the Unicodes which belongs to Yi Radicals block
Characters like ꒐,꒑,꒒, etc. are listed under Yi Radicals Block.
56 Characters are present in Yi Radicals Block starting with the Unicode point U+A490 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.