The STIHL ROLLOMATIC® E Light guide bar is a general-grade laminated guide bar made of high-grade steel. "Made of two hollowed out steel plates electrically welded together—this is 30% lighter than the standard bar. To reduce weight, it is completely hollowed out after being welded and is filled with fiber-reinforced polymide, making this bar up to 38% lighter as compared to the STIHL ROLLOMATIC® E. This bar has excellent rigidity for efficient cutting and better balance during limbing operations. A sprocket is incorporated in the nose of the bar that carries the saw chain from the top to the bottom of the bar. This not only reduces wear, but also enables the bar nose to be made considerably narrower. This type of construction is an advantage where extensive use is made of the bar nose (i.e. limbing and boring). All STIHL ROLLOMATIC® bars are designed with a narrow nose help reduce kickback tendencies. And the star-shaped sprocket can be replaced several times before the whole bar is due for replacement, increasing the bar’s service life. Applications: This bar is primarily intended for use by arborists. STIHL recommends using low-kickback, green-labeled chain and green-labeled reduced-kickback bars on all powerheads. Note: The actual listed guide bar length can vary from the effective cutting length depending upon which powerhead it is installed.