The disclosure relates to a system of circumferentially (preferably helically) arranging indicia on the elongate body of a medical device such as a catheter. The disclosure also relates to an anchor drain for securing a surgical drain to a fluid collection device. The anchor drain resists disconnection of the surgical drain from the fluid collection device and also resists occlusion of the conduit connecting the surgical drain and the fluid collection device, even when a suture is tied about a portion of the anchor drain inserted within the surgical drain, and resists unintentional withdrawal of the surgical drain from the body or a body cavity.