The invention relates to a breast pump kit comprising a breast pump collection system which is to be replaceable and detachable connected to an electrical driving unit during use. The breast pump collection system comprises a breast shield for placing on a breast of a user, a pump unit, and tubing connecting the breast shield to the pump unit. The pump unit comprises a compartment of a variable volume in fluid connection to the exterior only via the tubing. The pump unit is configured to be detachable combined to the driving unit such that a driving motion of the driving unit acts to alternatingly expand and contract the compartment of the pump unit. In this way the pump unit creates alternating suction and pressure in the breast shield and at the breast of the user when in use. The invention further relates to a breast pump collection system for use in such breast pump kit.
