Seldom is the ground surface flat or level enough for positioning a stand for a wind flag.  Post don’t care if the ground surface isn’t level, but eventually the top of the post must also be leveled.   Accurate performance of wind activity equipment require the mounting be leveled.  Wedges or blocks are normally not available, reliable or stable.  This is an unnecessary distraction and an area that we must be prepared to cope with and eliminate as a problem.  Some adjustable device between the stand or post and under the wind flag would be a big advantage.   It’s just another problem solving solution and control issue.
If your flag requires some off balancing to minimize the erratic action, an adjustable leveling device with a bubble level provides the means for that and to duplicate and repeat this setup action.  MTC bubble levels are machined and recessed into anodized aluminum holders for protection.  All MTC Trackers products have bubble levels incorporated into their design as standard features. 
MTC has included an adjustable leveling device on our Wind Flag, Cross Wind and Vertical Wind Trackers and several bubble levels.  Many are permanently attached and others used for setups.  There intention is to enable quick and accurate leveling adjustment at the point and time immediately prior to the need.  Larger adjustable leveler has the capability to hold and support up to (4) four pounds at an off angle position. The smaller adjustable leveler has (3) three pound capability. 
The leveling device alone is not available, they are included only with MTC Trackers and Bubble or Calibrated levels