AT&T MERLIN LEGEND System Reference Manual page 184

Features
Transfer
System Programming
The Transfer option of One-Touch Hold applies only to outside calls on a DLC
and not to calls on a QCC. When One-Touch Hold is programmed, if a system
operator presses a DSS button with an inside caller on the line or, in the
Hybrid/PBX mode, with an outside caller on a System Access button, the call is
not put on hold and a manual signal is sent to the extension corresponding to
the DSS button pressed.
When One-Touch Transfer (with either manual or automatic completion) is
programmed and the system operator presses the DSS button while the caller is
on the line and no Intercom or System Access button is available on which to
transfer the call, the call does not go on hold. If the system operator hangs up,
the caller is disconnected.
Assign or change the range of extensions represented by each Page button on
Direct Station Selector consoles.
SysRenumber -> Single
Direct Station Selector 2-135