Cone sleeves or collars are used to reflectorize traffic cones for use during hours of darkness.  Current MUTCD specs require 28" cones to have both a 6" and 4" band of reflective material for night use.  Although factory reflectorized cones are less expensive to purchase than adding sleeves to a non-reflective cone, Traffic Supply, Inc stocks self adhesive 6" and 4" sleeves for field repair and upgrade.  These collars will fit most brands of standard "wide" taper 18" and 28" traffic cones, but they will not fit "slim line" type cones.  Cone sleeves for narrow taper cones are available by special order.