Up to 3 Hours (Light Use): these products are designed for light office/domestic use up to a maximum of approximately 3 hours per day
Up to 5 Hours (Moderate Use): these products are designed for light office use up to a maximum of approximately 5 hours per day
Up to 8 Hours (General Use): these products are designed for use up to approximately 8 hours per day within normal office environments
Up to 24 Hours (Sustained Use): these products are designed to meet the more demanding environments and uses such as control rooms and call centres - they are rated to 25 stone and/or can be used for 24 hours each day