l16f1.dat
First Record: 125:18:15:15::     Last Record: 125:22:04:18::

l17f1.dat
First Record: 125:22:04:47::     Last Record: 125:01:57:07::

l19f1.dat
First Record: 126:07:21:02::     Last Record: 126:11:31:47::

l20f1.dat
First Record: 126:11:32:39::     Last Record: 126:12:29:51::