This is "W Gliding3 81" in the 8.1 library (not downwards compatible with 7.0, unfortunately).
Looking back into the 7.0 library, I didn't realize how many things had been added in 8.1... as well as better organization (why the double slider is in the 'casement' folder in 7.0 is beyond me).
Can you make do with the "W Triple Sash 70" window in the Casement Windows 70 folder? The 2D symbol looks OK (a bit odd, actually, but OK); if you turn 'opening line in 3D on', it shows hinging (of course), so you could just leave that off and draw the slide arrows manually if those are required in elevations?
Karl
One of the forum moderators
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