A ferrule includes a flange and an elongated sleeve extending from the flange. The flange and the elongated sleeve define a bore, which is configured to receive a length of flexible tubing. The elongated sleeve is configured to hold the flexible tubing within the bore via friction. For example, the elongated sleeve is configured to hold the flexible tubing within the bore without compressing the flexible tubing. In this manner, flow through the flexible tubing may be unrestricted. In some embodiments, a distance of flexible tubing contacted by the elongated sleeve is sufficient to hold the flexible tubing within the elongated sleeve without tightly holding or compressing the flexible tubing. This configuration can prevent narrow tubing from becoming blocked and/or the tubing bore can remain smooth (e.g., for accurate mixing, constant fluid flow, and so forth).