Wood'sPowr-Grip Vacuum Cups have a pump built into the end that pulls out the air and sealsthe cup onto the glass. Pump the brass plunger until the red line is hidden and the cupis secure. If the cup loses vacuum the red line appears and serves as a warning thatvacuum is being lost.
- Do not lift in excess of 70 pounds with this cup.
- Made in the USA.
