The 3M HL100 is a versatile headlamp that allows hands free lighting in certain industrial uses. Lightweight, 4 LED, 70 lumen, task light with 4 lighting modes that can be worn with or without 3M hard hats. Weighing only about 78 grams but able to run up to 150hrs on low setting and 74hrs on its high setting, this water resistant (IPX-4 rated) hard hat mounted head lamp is popular for a wide range of indoor/outdoor industrial lighting applications. It is not intrinsically safe. Comes with 3 AAA batteries and three attachment options. The rubber headband provides a secure attachment for the headlamp to most 3M hard hats. The 3M(TM) Dual Lock fastener works well for securing the headlamp to many hard hat designs and materials. Providing a strapless attachment option allows the headlamp to be secured without it interfering with earmuffs and other hard hat attachments. Securing the headlamp without at strap reduces interference with earmuffs and other hard hat attachments. The nylon headband allows the lamp to be worn by the user without wearing a hard hat.