Pumps air, too. From Parker, this unused takeout 12VDC double air/gas diaphragm pump draws 100-200mA and can push 28psi or suck 25"/Hg through two sets of 3/16” dia barbs. Long-life and ideal for high-flow and low-noise applications. Measures 3-5/8" x 3" x 1-1/4". Made in USA. Part#D861-22-OZ

This 12VDC muffin fan has (7) blades and measures 3-3/16” square x 1” with (3) 4” leads connected to an 8mm Molex connector. Draws 180mA, spins at 3200 rpm and pushes 36cfm. Has 3/16” mounting holes on the corners. UL.

Nice little 24VDC, 3-blade muffin fan from Nidec™ draws 70mA and pushes 31cfm. Measures 3-1/8" square with 4mm mounting holes on the corners, and a pair of 13” leads. Manufactured right here in the US of A.

This vacuum pump from Koge Electronics draws 100-250mA at 4.8V and is rated for >2.6L/minimum output and -460mbar of pressure. Measures 2-9/16" x 1-3/16" x 1-5/16" with a 3/16" OD x 3/8" inlet barb and a 3/16" OD x 1/2" tall outlet barb, plus (4) 1/8” ID mounting wings. Power terminals are exposed and you may get short leads. Koge model #KPV276.