Hello there,
have a flatside in my collection, Number 23xxx, it is the second variation with the late trigger and rear sight leaf.
<a href="http://forums.lugerforum.com/lfupload/c96_flat_li.jpg" target="_fullview"><img src="http://forums.lugerforum.com/lfupload/c96_flat_li.jpg" width="400" alt="Click for fullsize image" /></a>
<a href="http://forums.lugerforum.com/lfupload/c96_flat_re.jpg" target="_fullview"><img src="http://forums.lugerforum.com/lfupload/c96_flat_re.jpg" width="400" alt="Click for fullsize image" /></a>
<a href="http://forums.lugerforum.com/lfupload/c96_flat_oben.jpg" target="_fullview"><img src="http://forums.lugerforum.com/lfupload/c96_flat_oben.jpg" width="400" alt="Click for fullsize image" /></a>
<a href="http://forums.lugerforum.com/lfupload/c96_flat_unten.jpg" target="_fullview"><img src="http://forums.lugerforum.com/lfupload/c96_flat_unten.jpg" width="400" alt="Click for fullsize image" /></a>