Key Takeaways

• Match the fitting’s stated conduit compatibility and trade size to the conduit being installed.
• Choose a straight or angled configuration based on the entry direction and available installation space.
• Specify material, thread type, and environmental requirements, including any sealing or corrosion-resistance needs.
• Request product drawings and applicable ratings for the exact model before approving a purchase.

Who This Guide Is For

This guide is for electrical contractors, equipment manufacturers, distributors, and purchasing teams comparing flexible metal conduit fittings. It is useful when preparing a bill of materials, checking a replacement part, or sourcing fittings for a new project. Because product dimensions and approvals differ by manufacturer and model, use this information as a selection framework rather than as a substitute for the product specification.

What Flexible Metal Conduit Fittings Do

A fitting creates a mechanical connection between a flexible conduit and another component, such as an electrical enclosure. Depending on its design, it may also provide strain relief, help maintain a secure entry, or support a seal at the connection. The level of protection depends on the complete assembly and its stated product ratings, not just on the fitting’s appearance.

Typical applications include machinery connections, control panels, lighting equipment, and wiring routes where some flexibility is needed for installation or servicing. For wet, dusty, corrosive, or outdoor environments, verify the suitability of the fitting, conduit, enclosure entry, and installation method together. Do not assume that every metal fitting is liquidtight or suitable for every exposure.

Types, Materials, and Key Specifications

Common Fitting Configurations

• Straight fittings: Provide a direct entry into an enclosure and are often selected when the conduit approaches the entry in line with it.
• 90-degree fittings: Turn the conduit at the connection point and can help where a straight entry is impractical. Check the bend and clearance requirements for the installation.
• Liquidtight fittings: Designed for use with specified liquidtight flexible conduit. Confirm the exact conduit construction and environmental rating required; the fitting alone does not establish a system rating.
• Threaded or compression-style fittings: Use different connection methods to secure the conduit. Select only a design that is compatible with the conduit and installation procedure.

Materials and Finishes

Fittings may be offered in materials such as zinc-plated steel, aluminum, or stainless steel, depending on the product range. Material choice affects factors including weight, corrosion considerations, and compatibility with the installation environment. A finish may add a protective surface, but its suitability should be confirmed against the project conditions and manufacturer documentation.

As a supplier of aluminum pipes and related products, we understand that material selection is part of a broader sourcing decision. However, an aluminum fitting should not be treated as interchangeable with a steel or stainless-steel option without checking the required mechanical and environmental specifications. Ask for the material grade or finish details applicable to the specific product.

Sizes, Threads, and Fit

Flexible conduit fittings are commonly identified by trade size, but trade size is not necessarily the same as a measured outside diameter. For example, 1/2 in, 3/4 in, and 1 in are familiar trade-size references used in many conduit product ranges. These examples do not confirm that every fitting style or supplier offers all three sizes.

Check the fitting’s stated conduit size, enclosure-entry thread, and thread standard. A nominal size match alone may not guarantee that the fitting engages correctly with the enclosure or accepts the conduit. Where an existing installation is involved, provide the product marking, drawing, or measured details to reduce the risk of ordering an incompatible replacement.

SIOSAN Product Page

How to Choose the Right Fitting

1. Identify the conduit. Record its type, construction, and trade size from its label or technical documentation. Do not select a fitting based only on a visual estimate.
2. Define the connection points. Identify the enclosure entry, thread requirement, and whether the fitting connects directly to the conduit or needs an additional component.
3. Select the configuration. Choose a straight fitting for a direct approach or an angled option when the route requires a turn. Confirm available space and installation access.
4. Review operating conditions. Note exposure to moisture, dust, chemicals, vibration, or temperature variation where applicable. Request documentation showing whether the exact fitting is suitable for those conditions.
5. Verify documentation before ordering. Compare product drawings, dimensions, material details, installation instructions, and any required approvals with the project specification.

Common Selection Mistakes

A frequent mistake is treating all fittings with the same nominal trade size as equivalent. Conduit compatibility, entry threads, sealing features, and fitting geometry can differ, even when the size marking looks similar. Another risk is assuming that a liquidtight fitting makes an entire assembly liquidtight without checking the conduit, enclosure, and installation requirements.

Buyers may also overlook clearance around an angled fitting or fail to specify the material and finish. These omissions can lead to avoidable quotation questions or a product that does not match the application. Send the supplier the complete specification and request confirmation of any unclear interface before placing an order.

Pricing, MOQ, and Lead Time

Pricing depends on factors such as fitting type, size, material, finish, order quantity, and any packaging or documentation requirements. Minimum order quantities and production or shipping lead times vary by product and supplier, so they should be confirmed for the specific inquiry rather than assumed. If several sizes or configurations are needed, provide a line-by-line quantity schedule to support a clearer quotation.

For project purchasing, compare more than unit price. Confirm whether the quoted item matches the required drawing and specification, how products will be identified, and what information is available for inspection or incoming checks. These details help purchasing teams assess total sourcing suitability without relying on unverified performance claims.

Supplier Evaluation Checklist

• Can the supplier confirm compatibility with the exact conduit type and trade size?
• Are drawings or dimensional details available for the proposed fitting?
• Can the supplier state the material, finish, thread details, and applicable product ratings?
• Are MOQ, quotation validity, packaging, and estimated lead time clearly stated?
• Can the supplier review a sample, drawing, or project specification before order confirmation?

At SIOSAN, we encourage buyers to share application details, quantities, and technical requirements early in the sourcing process. This gives our team a basis to review the requested product scope and clarify information needed for evaluation. Product availability, customization options, and delivery timing should be confirmed against the specific inquiry.

Conclusion: Confirm Compatibility Before You Buy

The right flexible metal conduit fitting is the one that matches the conduit, trade size, connection thread, configuration, material, and installation environment. Start by identifying the conduit and enclosure interface, then verify dimensions and product documentation for the exact model. This approach is more reliable than choosing by nominal size or appearance alone.

For your next step, prepare a specification with the fitting type, size, thread, material preference, application conditions, and order quantity. Send it to SIOSAN for a product review and quotation, and request drawings or other relevant documentation before final approval.