GENTLE USD Mini Reducer Union｜6mm to 4mm Step-Down Connector

• Ultra-Compact for Tight Routing: ~40% smaller and ~20% slimmer OD for dense layouts in control panels, behind-panel spaces, rail slots, jigs/fixtures, and robot wrists.
• Dual Push-to-Connect, Thread-Free: Both ends are push-in—no threads, no tape. Insert fully to the stop for instant locking and fast installs.
• One-Piece Inline Reducer (6→4 mm): Replaces "union + separate reducer," fewer fittings = fewer leak paths and cleaner assembly.
• Straight-Through, Lower ΔP: O-ring + metal collet provide vibration-resistant sealing; a straight bore helps stabilize flow and reduce pressure loss.
• Made in Taiwan, Dual Colors: Black or grey-white (-GW) for clean system matching and circuit ID.
• Applications: Step-down branches on automation and robot arms, in-cabinet jumpers, module-to-module links, quick temporary extensions, and trunk splices.

Q1: How does USD differ from US?
A: US is a same-diameter inline union; USD is a reducing union that provides an inline 6→4 mm step-down, eliminating a separate reducer to lower fitting count and leak risk.

Q2: What tubing sizes and materials are supported?
A: The two ends interface 6 mm ↔ 4 mm metric tubing; compatible with PU and nylon (PA).

Q3: Do I need thread sealant or PTFE tape?
A: No. USD is thread-free, push-to-connect on both ends. Insert fully to the stop to achieve airtight sealing.

Q4: What is the recommended installation procedure?
A: Use a tube cutter to cut square, deburr, clean/dry the tube → push fully to the stop → perform a light pull-check → pressure-hold/leak-test (you may use diluted neutral soap solution if needed). For removal, press the release ring evenly—do not force-pull.

Q5: Is there a required flow direction or orientation?
A: No fixed flow direction. The two ends are different sizes but functionally equivalent—choose inlet/outlet based on your layout and avoid unnecessary sharp bends.

Q6: Can it be reconnected? Any usage tips?
A: Yes. Before reinsertion, re-cut a fresh section and ensure the tube end is square, clean, and dry. If you notice leakage or reduced grip, replace the entire fitting.

Q7: What operating pressure/temperature and media are supported?
A: Reference 0–0.9 MPa and 5–60 °C, primarily for compressed air. For vacuum or liquids, verify media compatibility and cleanliness, and validate on your equipment before deployment.

Q8: Any advice for high-vibration or moving assemblies?
A: Secure the line near the fitting with tube clamps/tie mounts to shorten unsupported spans and reduce fatigue. Observe the tube's minimum bend radius during routing.

Q9: How should I troubleshoot a minor leak?
A: Check in order: (1) Full insertion with a passed pull-check; (2) tube end is square-cut, burr-free, and unscratched; (3) no debris around the release ring area. If needed, re-cut and reconnect, then repeat the pressure-hold test.

Q10: What color options and identification practices are available?
A: Available in black or grey-white (-GW) to support circuit/equipment color coding. Made in Taiwan for durable quality and easy standardization in spare-parts management.