1. Small stem and long
- Increase sensitivity where the scale are far apart so the small changes in density can be detected

2. Glass wall
- Do not erode and small edhesive force

3. Lead shots
- Hydrometer can stay upright

4. Large diameter of bulb
- Bigger upthrust

5. scale can be made bigger or smaller than the density of water
- ability to measure wider range of densities of liquids *im not very sure for this option