Serial Numbers 1,175,001 through 1,443,170 (total production approximately 60,000); Viewfinder magnification 0.72X duplicating that of the M2 which enjoyed unexpectedly great popularity due to its modest wide angle lens capability; Bright-line frames for 35mm, 50mm, 90mm, and 135mm

The M4 (sans P or 2) is regarded by many Leica aficionados as the last and most highly evolved (and hence most desirable) of the classic first generation of meticulously internally engineered M's. Other than the M5, which has been widely faulted for its "big hands" departure from miniature physical size, it was the last Leica M to employ a multitude of "fine tuning" internal adjustments before Leica went to the more modern "replace and toss the worn part" approach employed in the M4-2, M4-P and all of Leica's subsequently introduced M bodies (except for the M6J). In many ways the M4's internal mechanism with its brass rather than steel gears is far more closely related to that of the M3 and M2 than it is to that of the M4-2 or the M4-P. In operation it feels noticeably smoother and more refined in its handling and film advance action.

The most obvious external change is the canted rewind knob which brought a non trivial improvement to this previously more tedious chore. More significant is the change to a lower viewfinder magnification which permits the use of the M4's multi frame finder to encompass a 35mm view. This, since it come at the expense of reducing the effective triangulation base, diminishes the precision of focus making focusing such lens genres as the f1.0 Noctilux or f1.4 75mm more problematic. There are almost always trade offs to such evolutionary steps that are not entirely positive.

Also important is the M4's new, for Leica, rapid and easy film loading scheme that replaced Leica's archaic and clumsy spool to spool system.

Only about 60,000 M4's were produced compared to about 4 times as many M3's and 1 1/2 times as many M2's. For a great many Leicaphiles the M4 is the last of the "REAL" M's produced. The M4 has taken on a real premium in the marketplace with both users and with collectors.

Below are the sales figures for the nine year life span of this camera body; except as noted all are chrome:

1967: 10,000 (incl. 100 that were Canadian assembled)
1968: 17,990 (incl. 620 black enamel and 150 motor coupling equipped, in black enamel)
1969: 12,155 (incl. 2700 black painted and 255 motor in black enamel)
1970: 12,371 (incl. 1030 black enamel, 30 olive green enamel and 400 motor in black enamel)
1971: 600 (500 black painted and 100 motor also in black enamel)
1972: 505 (all black enamel E Leitz Canada produced KE-7's*)
1973: NONE
1974-5: 5,820 Total, all black chrome, 1750 of which were produced by E. Leitz of Canada

*KE-7 is a special black enamel edition of the camera produced for the US Army that was fitted with special seals to keep dust and moisture out and employed special lubricants for very low ambient temperature shutter operation.