Mesh / SubD
Edit Tools > Stitch
The Stitch command matches the positions of a pair of mesh/SubD vertices.
Select the first set of edges, press Enter.
Or, select the first vertex.
Select the second set of edges, press Enter.
Or, select the second vertex.
The number of edges in both sets must match.
Pick the stitch location. Press Enter to stitch at the average location.
Or, select a stitch location option in the command-line.
If the vertex or edge pairs belong to different objects, the two objects will be combined into a single object.
Display SubD in Flat Mode by pressing Tab to help picking SubD vertices.
Use preselect to stitch multiple vertices.
Click selects a single edge. Double-click selects an edge loop.
Ctrl+click deselects a single edge. Ctrl+double-click deselects an edge loop.
Click an edge to select an edge loop.
The clicked edge displays a brighter highlight than the other edges in the loop.
Ctrl+click the same edge to deselect the loop.
The Edges option also allows selecting a pair of vertices.
Right-click to stitch at the average location.
Stitch at the location of the first set.
Stitch at the location of the second set.