32 characters in the CJK Compatibility Forms Unicode block.
U+FE30PRESENTATION FORM FOR VERTICAL TWO DOT LEADERU+FE31PRESENTATION FORM FOR VERTICAL EM DASHU+FE32PRESENTATION FORM FOR VERTICAL EN DASHU+FE33PRESENTATION FORM FOR VERTICAL LOW LINEU+FE34PRESENTATION FORM FOR VERTICAL WAVY LOW LINEU+FE35PRESENTATION FORM FOR VERTICAL LEFT PARENTHESISU+FE36PRESENTATION FORM FOR VERTICAL RIGHT PARENTHESISU+FE37PRESENTATION FORM FOR VERTICAL LEFT CURLY BRACKETU+FE38PRESENTATION FORM FOR VERTICAL RIGHT CURLY BRACKETU+FE39PRESENTATION FORM FOR VERTICAL LEFT TORTOISE SHELL BRACKETU+FE3APRESENTATION FORM FOR VERTICAL RIGHT TORTOISE SHELL BRACKETU+FE3BPRESENTATION FORM FOR VERTICAL LEFT BLACK LENTICULAR BRACKETU+FE3CPRESENTATION FORM FOR VERTICAL RIGHT BLACK LENTICULAR BRACKETU+FE3DPRESENTATION FORM FOR VERTICAL LEFT DOUBLE ANGLE BRACKETU+FE3EPRESENTATION FORM FOR VERTICAL RIGHT DOUBLE ANGLE BRACKETU+FE3FPRESENTATION FORM FOR VERTICAL LEFT ANGLE BRACKETU+FE40PRESENTATION FORM FOR VERTICAL RIGHT ANGLE BRACKETU+FE41PRESENTATION FORM FOR VERTICAL LEFT CORNER BRACKETU+FE42PRESENTATION FORM FOR VERTICAL RIGHT CORNER BRACKETU+FE43PRESENTATION FORM FOR VERTICAL LEFT WHITE CORNER BRACKETU+FE44PRESENTATION FORM FOR VERTICAL RIGHT WHITE CORNER BRACKETU+FE45SESAME DOTU+FE46WHITE SESAME DOTU+FE47PRESENTATION FORM FOR VERTICAL LEFT SQUARE BRACKETU+FE48PRESENTATION FORM FOR VERTICAL RIGHT SQUARE BRACKETU+FE49DASHED OVERLINEU+FE4ACENTRELINE OVERLINEU+FE4BWAVY OVERLINEU+FE4CDOUBLE WAVY OVERLINEU+FE4DDASHED LOW LINEU+FE4ECENTRELINE LOW LINEU+FE4FWAVY LOW LINE