LRECL specification - Key = '0042'

DALLRECL specifies the actual or maximum length, in bytes, of a logical record. When you code this key, # must be one, LEN must be two, and PARM contains one of the following values:
X'8000'
Variable length spanned records processed under QSAM and BSAM, the logical records exceed 32,756 bytes (X)
X'nnnn'
The logical record length. The maximum value for nnnn is '7FF8' (32,760).
Example: To specify a logical record length of 80, code:
KEY    #      LEN    PARM
0042   0001   0002   0050