If the total unit count is uncertain, indicate this with a question mark following the unit count.

300 ## $a 3 film reels of 3? (29 min., 2,584 ft.) : $b si., col. ; $c 35 mm. $3 interneg.

Include a note as needed.  See 7B14.

500 ## $a Possible film reel count from leader. $5 DLC (Use institution’s local code.)

If a work’s original length in units is not known, but the units in hand appear to be a part of a completed production (not stock footage, unedited film, etc.), regardless of whether it was released or broadcast, state the number of units in hand and substitute a question mark for the total number of units.  For treatment of works never intended to be distributed, see 5B6.

300 ## $a 2 film reels of ? (r2-3) (16 min., 1,450 ft.) : $b si., b&w ; $c 35 mm. $3 master pos pic.

300 ## $a 1 videocassette of ? (Hi-8) (40 min.) : $b sd., col. ; $c 8 mm. $3 viewing copy.

See also:

5B.  Extent of work and specific material designation

5.  Physical Description Area