The STL10507683 Irwin Strait-Line Chalk Line Kit comprises a chalk line and 113g blue chalk. The Irwin Chalk Line has a heavy-duty case which is constructed of durable aluminium alloy. It has a steel plated hook and large grip anchor ring which provide better holding power. Its retractable self-locking metal handle allows reel to be used as a plumb bob. Its twisted cotton line holds more chalk for multiple line strikes. Holds approximately 55g of chalk. Line length: 30m.