They call it the slide block pin.

[Red Cent]

Checking out some sites for disassembly of a Glock 34. Did net search. Always showed me the slide lock release pin or other horizontal pin.

Whare is it located?

[JR]

Sorry, I cant figure out what you have in your pic? There is no such thing as a slide lock release pin.
Take a look at the parts schematic on our web site http://www.lonewolfdist.com/SchematicsList.aspx?PAGE=Parts then tell me what part number you have?