Review on UMEI Aluminum Luminous Precision Horizontal by Kendro Givens

These levels are not correct when received. I have two. This fluorescent and a standard both in one package and both go out for 15-30 minutes. Test: Put them on a flat surface and rotate them 360, bubble error and direction should stay the same. It's not like this. I lay them on sandpaper on a flat surface and gently sand the base until no error/change of direction can be seen on the bubble, then in a solid aluminum case they are well and accurately levelled. I use a glowing level to level my telescope mounts in the dark and it doesn't seem to affect my night vision.