Marshall Electronics V-4325 25mm F2.5 M12 Miniature Glass Lens

The V-4325 is the long end of Marshall's 4300 series of M12 glass lenses. At 25mm it frames roughly ten degrees across on a 1/3 inch sensor, which is the reach you want when a board or bullet camera has to pick out a face at a doorway, read a gauge across a plant floor, or hold a tight machine-vision field without moving the camera closer.

Four glass elements sit in a threaded M12 x 0.5 barrel, the standard mount on Marshall's board and bullet cameras, and focus is set by hand at install. It focuses down to 20 cm, weighs 18 g, and covers both 1/3 inch and 1/4 inch formats.