Portable multifunctional tool comprising a handle portion and a tool accommodating portion having at least one tool function element (100, 200) arranged thereon, the tool function element (100, 200) being configured to actuate a quick release chain fastener (502, 1000) comprising two chain link plates (1001A, 1002A) and two chain link plate connection means (1001B, 1002B), and the tool function element (100, 200) comprising: first force exertion means (101, 201) configured to exert a force (F 1, F 2) on the first chain link plate connection means of the quick release chain fastener (502, 1000), and second force exertion means (102, 202) configured to exert a force (F 1, F 2) on the second chain link plate connection means of the quick release chain fastener (502, 1000), the first force exertion means (101, 201) and the second force exertion means (102, 202) being translationally moveable in relation to each other so as to actuate the quick release chain fastener (502, 1000) by means of this translational movement, and the tool function element (100, 200) comprising linear guide means (801, 802) having a stationary first linear guide element and a second linear guide element movably arranged within the former, at least one of the two force exertion means (101, 201; 102, 202) being arranged on the second linear guide element, wherein at least one of the two force exertion means (101, 102; 201, 202) comprises an accommodating portion (211, 212) for accommodating the quick release chain fastener (502, 1000), said accommodating portion (211, 212) being configured to avoid tilting of the quick release chain fastener (502, 1000) along the longitudinal chain axis, wherein the accommodating portion (211, 212) comprises an engagement portion (213, 214) configured to engage between two chain link plates (505, 506; 507, 508) of a chain link (501, 503) adjacent to the quick release chain fastener (502, 1000) when the quick release chain fastener (502, 1000) is arranged within a chain, and wherein the tool function element (100, 200) further comprises a rivet breaking pin for opening and riveting a riveted chain. a handle portion and a tool accommodating portion having at least one tool function element (100, 200) arranged thereon, the tool function element (100, 200) being configured to actuate a quick release chain fastener (502, 1000) comprising two chain link plates (1001A, 1002A) and two chain link plate connection means (1001B, 1002B), and the tool function element (100, 200) comprising: first force exertion means (101, 201) configured to exert a force (F 1, F 2) on the first chain link plate connection means of the quick release chain fastener (502, 1000), and second force exertion means (102, 202) configured to exert a force (F 1, F 2) on the second chain link plate connection means of the quick release chain fastener (502, 1000), first force exertion means (101, 201) configured to exert a force (F 1, F 2) on the first chain link plate connection means of the quick release chain fastener (502, 1000), and second force exertion means (102, 202) configured to exert a force (F 1, F 2) on the second chain link plate connection means of the quick release chain fastener (502, 1000), the first force exertion means (101, 201) and the second force exertion means (102, 202) being translationally moveable in relation to each other so as to actuate the quick release chain fastener (502, 1000) by means of this translational movement, and the tool function element (100, 200) comprising linear guide means (801, 802) having a stationary first linear guide element and a second linear guide element movably arranged within the former, at least one of the two force exertion means (101, 201; 102, 202) being arranged on the second linear guide element, wherein at least one of the two force exertion means (101, 102; 201, 202) comprises an accommodating portion (211, 212) for accommodating the quick release chain fastener (502, 1000), said accommodating portion (211, 212) being configured to avoid tilting of the quick release chain fastener (502, 1000) along the longitudinal chain axis, wherein the accommodating portion (211, 212) comprises an engagement portion (213, 214) configured to engage between two chain link plates (505, 506; 507, 508) of a chain link (501, 503) adjacent to the quick release chain fastener (502, 1000) when the quick release chain fastener (502, 1000) is arranged within a chain, and wherein the tool function element (100, 200) further comprises a rivet breaking pin for opening and riveting a riveted chain.