the hand-held pump 56

While the hand-held pump 56 is the first choice, due to its portability and reasonable cost, other types of vacuum pumps may be utilized. Almost any type of mechanical pump may be used for  hand-painted oil painting evacuation, as long as it includes a suitable interfacing valve adapter 60. Rotary vane, diaphragm, piston type vacuum pumps are readily available in the oil-free style rated for coarse vacuum, that is up to 28 inches  of mercury. It should be noted that the oil-free type is advisable, as the oil mist lubrication in some fine and high vacuum pumps may contaminate the paint with small quantities of mineral based oil.

Hook means permit the hanging of a wet brush 30 within the domed lid to prevent the bristles from being bent during storage. illustrates a single hook 62, preferably made of a C-shaped wireform Oil Paintings  attached into the lid recessed valve cavity 22. This hook 62 completely removed from the invention. While only one hook is illustrated penetrating a pair of holes 64 in the cavity 22, multiple hooks 62 may be used with equal ease interfacing with the lid 20 with brackets, or the like, permitting more than one brush 30 to be retained.

For convenience, vacuum pump storage means may be integrally formed into the external surface of the domed lid 20 in the form of a pair of pump mounting brackets 66. These brackets 66 are configured to hold a manual vacuum pump 56 of the type  through 3, and 11, and are sized to permit a snap fit for retension, as the thermoplastic material of the lid has adequate resilience.
(article source:Oil Painting)