Screen Innovations Nano Roll 275 Series Installation Instructions Manual page 5

SPACER BLOCKS AND LEVELING SHIMS (OPTIONAL)
Spacer Blocks - used to clear an obstruction in the fabric path.
Connect spacer blocks to shade brackets before installation.
Note: Do not use more than 4 spacer blocks per bracket.
Leveling Shims - used if the window frame is out of level.
Connect to shade brackets before installation
Note: Do not use more than 2 leveling shims per bracket.
Spacer Blocks and Leveling Shims (Optional) 4