Use this CRL Wood's Powr-Grip® Vacuum Cup with Cleat Head to mount cameras, scopes, and camcorders with standard 1/4"-20 threads to provide a reliable, temporary vacuum mount without drilling holes. The 4-1/2" (114 mm) rubber vacuum pad will not mark or damage flat or curved smooth non-porous surfaces. The red-line indicator warns the user of any vacuum loss, and the check valve allows re-pumping without loss of the remaining vacuum. Lift tabs on the vacuum pad edges permit instant release. Supplied with a vacuum pad protector.