1. Purpose

Stubs a short pipe length out of a fitting's free connector, sized by the connector (300 mm baseline), to reach the run it must join. No hand-drawn stub plus manual alignment to the connector.

2. Quick video (≤ 2 minutes)

[Video in production — follow the steps below for now.]

3. Steps

Open a view showing the fitting with a free end (an unconnected End connector). [image 01: fitting with a free connector]
Click Extend in the VP_MEP tab, Common panel.
Pick the fitting when asked.
For each system domain (water/air/power) lacking a sample, pick 1 sample pipe of that domain when asked — the tool learns the pipe type from it. [image 02: picking a per-domain sample pipe]
The tool builds a stub from each free end along the connector direction, sized by the connector (300 mm baseline), and joins it into the fitting.

4. Real-world example

A DN80 transition elbow has one free end 200 mm short of the main. Run the command, pick the elbow, pick a water sample pipe — a DN80 stub grows along the connector direction and joins the elbow; just continue the main from there.

5. Common errors

Symptom	Fix
"Phụ kiện không có connector hợp lệ."	The pick isn't a connectored fitting — recheck
"Không có connector trống để kéo dài."	Every end is already joined — this command only serves free ends
"Thiếu phần tử mẫu cho miền tương ứng."	Pick 1 sample pipe of the matching domain when asked

6. See also

Quick-connect MEP ends — join the fresh stub into the main run.
Resize a duct keeping its area — size before extending.
Split a gap on the run — open an expansion gap on the new segment.