A traffic channelizer device includes a deformable hollow plastic drum that may be ballasted by a drop over ballasting collar or by a base having an upper portion that may be releasably retained within the open bottom of the drum by a plurality of circumferentially spaced radially inwardly extending locking fingers adjacent the bottom edge of the drum that releasably engage a groove in the upper portion of the base. An intermittent stacking rim may be provided at the top of the drum to prevent overstacking of a plurality of such drums. Also the intermittent stacking rim may be used to prevent rotation of a portable sign assembly relative to the drum and keep the portable sign assembly from inadvertently sliding up off the drum top.
