How do you prevent leakage and cap loosening for eye serum droppers in U.S. shipping?

Quick Answer (for busy buyers)

Here’s the buyer-first summary. If your brand name is on the label, you usually act as the responsible person and must ensure the listing is submitted and kept current.

• For droppers, leakage and cap loosening usually come from mismatch between bottle neck finish and closure, insufficient cap torque, or no secondary seal.
• We typically lock the system by confirming the bottle/closure spec (glass or acrylic), setting a torque standard during filling, and using a suitable liner/wiper insert.
• For transit protection, we recommend a tamper-evident band or secondary sealing method plus a tight inner tray so the dropper is not side-loaded.
• For Amazon US shipping, we also design the pack-out: individual unit protection (polybag or sleeve), divider/tray to keep droppers upright, and a stronger master carton to reduce vibration.
• We can support packaging design and matching services, plus arrange packaging checks (typical packaging testing lead time is 3 days) and product send-out testing with report tracking.
• MOQ is typically 1000-3000 pcs (simple items can start at 1000).
• After sample confirmation, mass production lead time is usually 10-20 working days.
• Packaging ordering often takes 10-30 working days (e.g., glass bottle 15 days, acrylic 30 days; single box 15 days, set box 20 days), so we plan both streams in parallel to reduce risk.