Light under Wall Units

We purchased a 3 pack of surface mounted coll white LED lights for below one set of wall cupboards ( we would have had 2 sets but the price at £49 seemed a rip-off). These light were actually supplied by Sycamore Lighting Ltd., of Swillington, W Yorkshire so presumably Wren applied some mark up. The lights supplied were a bit odd as there were 2 screws with each light but nothing to screw on to and the back of the lights were quite sticky with the remains of some residual adhesive so clearly the lights had been re-worked before we got them. 3M self-adhesive pads were provided for attaching the lights to our units and they seem to work, they haven't fallen off yet.