Products in this family are assortments of heat shrinkable insulating tubing, from a single manufacturer and product series but varying in size and/or color, offered in kit form to provide a convenient means of acquiring a range of product likely to be found useful in the course of maintenance, repair, or product development operations. Different product series exhibit different characteristics, such as maximum ratio of pre- and post-shrink diameters, mechanical rigidity of the product after shrinking, and presence of an inner adhesive layer.