S. G. Gears will be capable of manufacturing double helical gear with a central groove and a Herringbone Gears or Double Helical Gears without a central grove i.e. a herringbone gear with an apex. Herringbone Gears or Double Helical Gears find application in steel rolling mills, cement industry etc. Herringbone Gears are used to balance the thrust load. A herringbone gear, a specific type of double helical gear, is a special type of gear which is a side to side (not face to face) combination of two helical gears of opposite hands. From the top the helical grooves of this gear looks like letter V. Unlike helical gears they do not produce an additional axial load.