Flatlock vs overlock seams in activewear: where each belongs

Buyer ranking for seam construction

This ranking orders the decisions that most directly affect seam construction; it does not rank named factories or products.

Read the table as a shortlist for discussion. The final decision should be recorded against the intended wearer, garment construction, destination market, approved sample and commercial quantity.

What buyers often misunderstand about undefined

Flatlock can reduce bulk where seams contact skin; overlock plus coverstitch is efficient and suitable for many areas. Choose by seam location, stretch, appearance and machine capability.

A single headline value cannot describe the whole garment. Composition, knit or weave, finishing, pattern geometry, seams, decoration and care conditions interact. Ask which variable changed, what stayed constant and which sample or report supports the answer.

What to put in the development brief

Write requirements as testable decisions rather than adjectives such as premium, breathable or durable. If the target is unknown, label it as an open development question and agree how the sample will be compared.

For a custom sportswear factory enquiry, connect undefined to the style code, colour, size range, logo route and order quantity. This keeps the answer usable when the project moves from quotation to sampling and bulk.

• Define the intended wearer and seam construction objective.
• Name the material, construction, color and size range.
• State the method or comparison process.
• Set an acceptance criterion and approval owner.
• Link the requirement to the current specification revision.

Sample and evidence plan

Inspect the inside and outside of a worn sample. Specify stitch type, thread, seam allowance and reinforcement zones.

Keep the physical sample identifier, specification revision, material reference, artwork file and approval comments together. A report for another material or a successful prototype does not automatically prove that later bulk goods are identical.

• Confirm the question and acceptance criteria before testing.
• Use the proposed bulk material and construction where practical.
• Record method, conditions, result, date and sample identity.
• Resolve failures or substitutions before bulk release.

Factory confirmation checklist

SenLin’s published order baselines remain standard styles at 100+ pieces and custom developments at 300–500+ pieces; the applicable allocation, material route and decoration minimum must still be confirmed in the quotation. Published baselines are not an automatic acceptance of every specification.

Decision and risk note

Proceed when the seam construction requirement, evidence and approval responsibility are clear. Pause if a change affects fit, claim wording, cost or delivery without written confirmation.

Regulations and buyer requirements vary by product and destination. Use qualified compliance advice where needed, and do not print a performance, fiber, sustainability or care claim until the responsible party has a reasonable basis for it.