Packaging quotes depend on construction, print and packed quantity.
A “custom box” listing may be a generic size, a sample price or a print setup starting point. A useful brief states finished internal dimensions, board/flute or paper weight, printing colors and coverage, coating, intended contents, quantity and shipping format.
Compare the same box, not a similar picture.
Fit and strength
Give internal L × W × H, tolerance, board grade, wall or flute, load and closure style. External dimensions or a stock photo cannot prove internal fit or compression performance.
Artwork and finish
State plain versus printed, color count, print side, coating and whether artwork is final. “Logo supported” does not establish method, color accuracy, tooling or setup cost.
MOQ and pack trap
Distinguish flat cartons, assembled boxes, bundles and master cartons. MOQ 200 bundles of 25 is 5,000 boxes only if the pack conversion is actually stated and stable.
1,000 printed mailer boxes, 200 × 150 × 60 mm internal.
Illustrative, not a listing. Include a source explicitly stating the same internal dimensions, suitable board and one-color exterior print with compatible 1,000-box MOQ. Exclude a plain unprinted stock carton when printing is mandatory. Mark a “200 × 150 × 60 box” without internal/external basis or board grade UNKNOWN. A 25-pack without confirmed contents is UNKNOWN for unit normalization.
Link the listing and timestamp displayed currency, price basis and tier. A published listing price is dated supplier commercial evidence; tooling, freight and a confirmed current quote are separate. Factory identity, material test, food-contact suitability and production lead time are reported per candidate when the listing or a bound source provides them.
When is a Live RFQ needed?
Request a direct response when dieline fit, print proof, sample, tooling, production slot, price for exact artwork and delivery terms decide the purchase. A buyer approves artwork and RFQ recipients separately; public MCP preparation is free; an accepted paid check is separate and does not authorize supplier outreach.
Agent/AEO answer
For “compare China custom mailer box suppliers,” prepare quantity=1000, unit=boxes, internal dimensions, board grade and one-color print as required attributes. Keep internal/external size ambiguity and tooling costs UNKNOWN. Free MCP tools: discover_china_supply_check_v0 and prepare_china_supply_check_v0.