I bought these to replace my old fluorescent lights in the workshop as they were going dim and showing signs of end of life. Before I changed them I also took a note of the electricity usage with them all switched on (12) of them. New tubes arrived promptly, were a straight forward replacement into the existing fittings with starters replaced with included led starters. The lights now come on immediately, no more flickering, with a much brighter natural type light. Really pleased with them and checking the electricity meter there is a noticeable reduction in power useage.