Colorists who need to measure a specific liquid volume — developer, color, or a diluted treatment — before combining it with another product in a bowl. Useful for anyone following a written, ratio-based formula, whether it's written in ounces or milliliters.

The dual-unit markings are the real point of difference: color and developer lines print mixing instructions in ounces or in milliliters depending on the brand, and this cylinder can be read against either without doing the math to convert one to the other.

• Pour the liquid to be measured — developer, color, or treatment — into the cylinder up to the required line
• Read the level at eye level for accuracy
• Pour the measured liquid into the mixing bowl using the spout
• Rinse the cylinder with water right after use so residue doesn't build up on the graduation markings

• Pro: markings in both ounces and milliliters mean it can be read directly against formulas written in either unit, with no conversion needed
• Pro: the spout controls the pour, reducing drips when transferring liquid into a bowl
• Pro: small and light enough to keep next to a color station without taking up counter space
• Con: the single 4 oz capacity means a job needing more liquid — a full head of bleach, for example — requires refilling and pouring more than once
• Con: the graduation lines are on the outside of the cylinder, so dried product residue can make them harder to read if it isn't rinsed out promptly