Draw the whole clamp arrangement
Use the exact arm and tray drawings. Mark each fitting on the desktop and draw a second view of the underside. Include lower plates, stems, handles and the space needed to turn a knob or insert a tool. A narrow upper pad can have a much larger fitting beneath the edge. Check the desk maker’s approved mounting area and material before placing either fitting.
Mark rear rails, drawers and cable holes on the same sketch. Include any reinforcement plates the arm maker approves. Measure the complete thickness through the top and plates when comparing the clamp range. Keep each plate flat against its approved support area and avoid arrangements where one clamp bears on another fitting.
Invision MX200 as the monitor-arm example
The selected MX200 supports one 19–32 inch screen weighing 2–9 kg and lists a 10–90 mm desk-thickness range. Check the weight without the original stand and confirm the hole pattern separately. Measure the lower clamp and the tightening room on your own edge. The thickness range cannot show whether a rail blocks the underside.
An everyday adjustable screen
Invision MX200
The gas-assisted arm suits a single compatible screen you move between tasks. It frees the desk from a broad stand and gives you a choice of edge clamp or through-desk fixing.
A centred clamp can leave the elbow in the way of the wall. Check whether the clamp can sit to one side while keeping the screen centred. Match the fitting diagram to the base supplied.
- 19–32″
- 2–9 kg
- VESA 75 × 75 or 100 × 100 mm
Move the arm to the positions you will actually use. Check where the elbow folds and where the display plugs sit. Cables from the arm need to reach their connection point with slack at the furthest position, including when the screen is turned.
Duronic CMH2 as the separate tray example
The CMH2 attaches with two edge clamps. Duronic gives a tray around 40 cm wide and a roughly 5–30 mm clamp opening. Measure both lower knobs and the loaded contents. A large power brick or plug can extend above the wire tray and reach the arm clamp even if the empty basket clears it.
For a flat, accessible edge
Duronic CMH2 clamp-on cable tray
Two screw-adjusted clamps hold the open steel basket against a compatible desktop edge.
Check both clamp pads have a flat landing spot. Allow room for the knobs and any monitor-arm fixing.
- Clamp-on
- 40 × 16 × 17 cm outer
- Approx. 5–30 mm clamp opening
Place a cardboard outline of the tray below the proposed edge, then mark both clamps. Keep the arm plate and tightening space outside those outlines. If the tray works only by blocking access to the arm knob or leads, move it along another approved section of the edge.
Check the combined setup before loading it
Follow both makers’ installation instructions and the desk’s fixing guidance. Confirm each clamp sits squarely on its own support area. Leave access to release or tighten each fitting independently. Put cables through the planned route before securing the final bundle, and check that the arm does not pull a lead across the edge of the tray.
On a moving desk, test the tray, arm and cables at low, high and intermediate positions. Also check the chair and your knees at the seated setting. If the two fittings cannot fit along the rear, compare a maker-approved screw location for the tray or another approved arm mounting method.
Common questions
How far apart should the arm and tray clamps be?
Use their actual footprints and tightening clearances. There is no single gap that covers different plates, knobs and trays.
Can two clamps share a reinforcement plate?
Ask the desk, plate and clamp makers whether that configuration is approved and how it must be loaded.
Does a clamp’s thickness range prove it will fit?
Check underside depth, rails, bevels and knob access as well as the complete thickness.
Can the tray touch the arm’s lower plate?
Give each fitting the independent support and clearance its instructions require. Reposition if the parts interfere.
What changes on a sit–stand desk?
Check the whole arrangement through the intended travel, including knee space, frame movement and fixed-to-moving leads.
Sources and selection
Sources and Amazon UK listings checked in November 2026. Fit examples use published specifications and measurements to take in your own room.