The invention relates to a blood lancet apparatus (101, 201, 301, 401, 501) with a base member (103, 203, 303, 403, 503) for the arrangement of apparatus components. These comprise a lancet-receiving device for holding at least one lancet element, which is surrounded at least locally by the base member (103, 203, 303, 403, 503), and a cap (102, 202, 302, 402, 502, 602, 702, 802, 902, 1102, 1202, 1302, 1402, 1502, 1602) coupled to the base member (103, 203, 303, 403, 503) for the arrangement of a setting wheel (104, 204, 304, 404, 504, 604, 704, 804, 1004) on a portion (626, 726, 826) of the cap (102, 202, 302, 402, 502, 602, 702, 802, 902, 1102, 1202, 1302, 1402, 1502, 1602) which is cylindrical at least in part, in order to set a plurality of exit lengths (Ll, L2, L3) of the lancet element out of the blood lancet apparatus (101, 201, 301, 401, 501). In addition, the setting wheel (104, 204, 304, 404, 504, 604, 704, 804, 1004) is produced with an internally threaded portion (624, 724, 824, 1524) and the cylindrical portion (626, 726, 826) has an externally threaded portion (628, 728, 828, 1328, 1528, 1628), wherein the threaded portions {624, 724, 824, 1524, 628, 728, 828, 1328, 1528, 1628) are connected to one another functionally in such a way that the setting wheel (104, 204, 304, 404, 504, 604, 704, 804, 1004) is rotatable and adjustable in the longitudinal direction (L) of the base member (103, 203, 303, 403, 503). According to the invention the setting wheel (104, 204, 304, 404, 504, 604, 704, 804, 1004) is surrounded by arm-liJce segments (318a, 418a, 518a, 318b, 418b, 518b) extending in the longitudinal direction (L), in such a way that an actuation of the setting wheel (104, 204, 304, 404, 504, 604, 704, 804, 1004) required for setting the exit length is capable of