A syringe for use in a drug infusion system, the syringe comprising: a barrel having a front end, a rear end, and a cylindrical wall defining an outer surface and an inner surface, the rear end being open, and the front end including an orifice; a plunger within the barrel, the plunger including a contact surface at a front end of the plunger, a rear end of the plunger having a tapered outer surface extending between a forward-facing undercut and the rear end of the plunger, a front seal gland extending circumferentially around the plunger, a rear seal gland extending circumferentially around the plunger and axially spaced to the rear of the front seal gland, the rear seal gland adapted to include a rear-facing undercut, a rear seal surface, and the forward-facing undercut, the tapered outer surface increasing in diameter from a surface of the forward-facing undercut to the rear end of the plunger, and a blind bore open at the rear end of the plunger and closed at the front end of the plunger and having a cylindrical portion and a plunger seat on a rear-facing side of a head of the plunger; a front o-ring made of a diene rubber compound, positioned in the front seal gland, and creating a gas-tight seal between the inner surface of the barrel and the plunger; wherein a product chamber is defined between the inner surface of the barrel, the front o-ring, and contact surface; wherein the product chamber is adapted to contain a product to be dispensed by the syringe; wherein actuation of the plunger within the barrel decreases the volume of the product chamber to dispense the product through the orifice; and characterized in that: the front o-ring is sized to maintain the gas tight seal through a temperature range of -25°C to 40°C. a barrel having a front end, a rear end, and a cylindrical wall defining an outer surface and an inner surface, the rear end being open, and the front end including an orifice; a plunger within the barrel, the plunger including a contact surface at a front end of the plunger, a rear end of the plunger having a tapered outer surface extending between a forward-facing undercut and the rear end of the plunger, a front seal gland extending circumferentially around the plunger, a rear seal gland extending circumferentially around the plunger and axially spaced to the rear of the front seal gland, the rear seal gland adapted to include a rear-facing undercut, a rear seal surface, and the forward-facing undercut, the tapered outer surface increasing in diameter from a surface of the forward-facing undercut to the rear end of the plunger, and a blind bore open at the rear end of the plunger and closed at the front end of the plunger and having a cylindrical portion and a plunger seat on a rear-facing side of a head of the plunger; a front o-ring made of a diene rubber compound, positioned in the front seal gland, and creating a gas-tight seal between the inner surface of the barrel and the plunger; wherein a product chamber is defined between the inner surface of the barrel, the front o-ring, and contact surface; wherein the product chamber is adapted to contain a product to be dispensed by the syringe; wherein actuation of the plunger within the barrel decreases the volume of the product chamber to dispense the product through the orifice; and characterized in that: the front o-ring is sized to maintain the gas tight seal through a temperature range of -25°C to 40°C.