Glass Tube Flowmeters provide optimized accuracy.
Press Release Summary:

Designed with magnifier lens and white tube background, Sho-Rate™ 1350 and 1355 provide accuracy to 5% and 3%, respectively. Both variable area meters also offer optimized repeatability from 0.5–0.25%. Custom direct read scale decals can be applied directly to tube, supporting unique flow ranges and units of measure.
Original Press Release:
Brooks Instrument 1350/1355 Glass Tube Sho-Rate Variable Area Meters
Engineered for rugged, durable, long-lasting performance, the newly enhanced Sho-Rate™ 1350 and 1355 glass tube flow meters incorporate features designed to make them more reliable and easier to use.
Tighter accuracy - the 1350 has improved its accuracy to 5% and the 1355 now offers 3% accuracy
Tighter repeatability - both models have improved repeatability from 0.5% to 0.25%
Improved readability, through the addition of a magnifier lens and white tube background
Custom direct read scale decals can be applied directly to the tube, supporting unique flow ranges and units of measure