A device for servicing a refrigerant system, comprising: a body comprising: a first fluid port, wherein the first fluid port is coupleable to a fluid port of a fluid source; a second fluid port, wherein the second fluid port is operatively coupleable to a refrigeration system; a passage extending through at least a portion of the body in fluid communication with the first and second fluid ports (311; 313); a plunger at least partially disposed in the passage of the body, wherein the plunger is adjustable between a released position and an engaged position, during use; and a plunger seal at least partially disposed in the passage of the body and configured to seal the second fluid port during use; and an actuator coupled to the body, and wherein, during use, downward movement of the actuator moves the plunger downward to open the fluid source while simultaneously adjusting a position of the plunger seal to allow substantially continuous fluid communication between the first fluid port and the second fluid port, characterized in that the plunger includes a piercing pin operable to open two types of fluid sources, the two types of fluid sources including a first type of fluid source which requires a seal to be pierced and a second type of fluid source which contains a self-sealing valve that requires a pin to be depressed. a body comprising: a first fluid port, wherein the first fluid port is coupleable to a fluid port of a fluid source; a second fluid port, wherein the second fluid port is operatively coupleable to a refrigeration system; a passage extending through at least a portion of the body in fluid communication with the first and second fluid ports (311; 313); a plunger at least partially disposed in the passage of the body, wherein the plunger is adjustable between a released position and an engaged position, during use; and a plunger seal at least partially disposed in the passage of the body and configured to seal the second fluid port during use; and a first fluid port, wherein the first fluid port is coupleable to a fluid port of a fluid source; a second fluid port, wherein the second fluid port is operatively coupleable to a refrigeration system; a passage extending through at least a portion of the body in fluid communication with the first and second fluid ports (311; 313); a plunger at least partially disposed in the passage of the body, wherein the plunger is adjustable between a released position and an engaged position, during use; and a plunger seal at least partially disposed in the passage of the body and configured to seal the second fluid port during use; and an actuator coupled to the body, and wherein, during use, downward movement of the actuator moves the plunger downward to open the fluid source while simultaneously adjusting a position of the plunger seal to allow substantially continuous fluid communication between the first fluid port and the second fluid port, characterized in that the plunger includes a piercing pin operable to open two types of fluid sources, the two types of fluid sources including a first type of fluid source which requires a seal to be pierced and a second type of fluid source which contains a self-sealing valve that requires a pin to be depressed.