I purchased the BoliOptics magnifying lamp with a 3 diopter lense, and purchased the 5 diopter lens shortly afterwards. I have been looking for this type of device with the 7 inch lens diameter, LED lighting element (dimmable), and arm length for a long time. It is great!!! The ability to swap two different lenses with 3 and 5 diopter increases the utility of this lamp substantially. I have constructed support bases on my primary work bench, my computer desk, my portable work table, and two different rollaround pedestals. I also purchased and modified a storage case for the two lenses which allow the empty lamp frame to be hung on pegboard when not in use.