Hi vis vest form an integral part of hi-vis workwear. These kinds of gear help in locating your position where visibility is quite low. If one is not sure of the other’s position, then there could be a co-ordination mismatch and one could face a mishap. Be sure to purchase good quality hi vis workwear.  http://www.workwarehouse.com.au/shop-online/workwear/hi-vis-workwear