this invention is about a string line holder , used by construction workers for aligning construction units , that is inexpensive to make because of its simplicity in structure and its material which string line holder , after the string line is used up or defrayed , can be completely disposed of and replaced by another inexpensive string line holder of the same structure . the string line holder is made from a cylindrically shaped reel or spool on which the string line is wound and has an elongated handle which can be entirely inserted within a cylindrical passageway through the reel or spool and can be partially withdrawn from the cylindrical passageway such that the reel or spool can be rotated around a portion of the elongated handle . the string line holder , including the reel or spool and the elongated handle , is constructed from an inexpensive material such as cardboard or plastic .