One more think to check - Does the SD have a 'locking nub' ?In the closed position check wether there is a little bump on the top of the SD right at the end.If yes it's after 1999 - If no it's before.
Excellent pics and explanation PabsThat feature really needs a pic to explain - I could not muster one up !!Re dates etc - Have you seen my dating sheet??https://forum.multitool.org/index.php/topic,51872.msg1214400.html#msg1214400I need to post a new version, there have been a few updates since this version - and some more info from El CS