Methods and devices for transferring materials between containers are discussed. One such connector includes: a base； a first elongate structure having first and second ends, the first elongate structure extending from a first side of the base at the first end to the second end distal the base, the second end forming a first opening sized and configured to receive a first container； a duct extending through the base and having a first tip skirted on one or more sides by the first elongate structure； a first guard positioned within the first elongate structure, wherein the first guard comprises a first surface, and the first surface is located further away from the base than the first tip. When the first container is moved into the first opening, the first surface moves toward the base, and the first tip enters the first container, creating a fluid path for the first container.
