If you are sourcing TWS earbud protective cases for resale, the supplier you choose decides your margin, your return rate and how fast you can restock. This guide covers what to check before you request a quote, which compliance documents actually matter, how to compare quotes that look different but are not, and the warning signs that a supplier will cost you more than the unit price suggests.
What to check before you request a quote
A one-line message asking for “your best price” usually produces a one-line reply that tells you nothing. Buyers who get useful quotes are the ones who ask four specific questions in the first message: what the minimum order quantity is for each model, how long dispatch takes, how the goods ship, and what the unit price includes. Everything else can be negotiated later.
Match the case to the charging case, not to a brand name
A TWS protective case is a moulded silicone or TPU shell cut to the exact outer dimensions of a charging case. Two charging cases that look similar in a photo can differ by two millimetres, and two millimetres is the difference between a case that grips and a case that falls off in a customer’s pocket. That is why a supplier’s catalogue entry is only useful if it states the fit clearly: the charging case shape it was moulded for, the material, the thickness, and whether the lid is a separate piece or a hinged shell.
KZYAO sells third-party protective accessories and deliberately does not use other manufacturers’ brand names in product titles or descriptions. Instead every listing publishes the fit and the construction, and we ask buyers to measure a charging case from their own stock before ordering a sample. If a supplier will not give you dimensions and will only tell you “it fits the popular models”, that is your first warning sign, not your first quote.
It is worth browsing a well-structured category before you write to anyone, so you know what a complete specification looks like. Wholesale TWS earbud cases and over-ear headphones on this site is a reasonable benchmark: each model lists the fit, the material and the MOQ next to a live unit price.
Confirm the real MOQ per model
MOQ is almost always quoted per model, not per order, and that distinction changes your entire first-order plan. A supplier might require 20 pieces of one case design, which means a four-model test order is 80 pieces, not 20. Ask explicitly: is the minimum per model, per colour, or per order? If a supplier says “per order”, ask what happens when you order one piece of six different designs.
Minimums also vary by how the product is made. Simple silicone sleeves usually have the lowest entry point because the tooling already exists. A model with a printed logo or a custom colour has a higher effective minimum because the production run has to be set up. On this site, most models start at 20 pieces, some at 10, and the smallest stylus sleeves start at 50 because they are cut from a different mould. The full picture is in wholesale MOQ and mixed-batch orders explained.
Ask about dispatch and shipping in the same message
Dispatch time is the gap between the payment clearing and the parcel leaving the warehouse. Transit time is everything after that. Buyers constantly confuse the two, then blame the supplier for a late delivery that was actually a slow customs lane. Ask for both numbers separately, and ask which carrier is used.
On this site the split is published openly: orders are dispatched in 3–5 business days after confirmation, and air express transit is typically 14–25 days depending on the destination. If you buy through your own freight forwarder in China, the dispatch window is the same but you organise the export leg yourself, which is usually the cheaper route once your volumes are steady.
Certifications and compliance that actually matter
Compliance is where cheap sourcing goes wrong most often. The three marks that come up in almost every purchase order for 3C accessories are CE, FCC and RoHS, and each one answers a different question.
CE — access to the European market
CE marking is the manufacturer’s declaration that a product meets the applicable European Union requirements. For a silicone earbud case the relevant directives are narrower than for anything with a battery or a radio, but customs and marketplace compliance teams still ask for the declaration. If you sell into the EU, ask which directive your product falls under and keep the paperwork with the product file.
FCC — access to the United States market
FCC rules apply to devices that emit radio frequency energy. A passive accessory that contains no electronics may fall outside the equipment authorisation rules entirely, while a case with a charging pass-through or a wireless coil will not. The honest answer to “is it FCC compliant?” is a question back: which model, and does it contain active electronics? Suppliers who answer with a blanket “yes, all our products are FCC certified” are not answering the question.
RoHS — restricted substances
RoHS restricts lead, mercury, cadmium, hexavalent chromium and certain flame retardants in electrical and electronic equipment. It matters most to buyers selling into the EU, and it is the document that is most often requested and least often actually held. Because silicone and TPU accessories sit close to the boundary of the scope, ask your supplier to state the position in writing for the specific material rather than sending a generic certificate.
What to request in writing
Certification belongs to a product, not to a company. A document issued for one model tells you nothing about a different one. Before you place a bulk order, ask for the compliance position for each model on your shortlist, in writing, and keep it with the purchase order. If you later list the product on a marketplace, that file is what your compliance team will ask for — and it is much harder to obtain six months after the order.
How to compare quotes fairly
Three suppliers can send three identical-looking unit prices and still be thousands of dollars apart on the same order. The difference is what each price includes.
Normalise the unit price first
Check the currency, check whether tax is included, and check the quantity the price is valid for. A price that only applies at 5,000 pieces is not a quote for your 60-piece test order, and a price quoted in a different currency is not comparable until you apply the same exchange rate to all three.
Then price the landed cost
The number that matters is what one piece costs when it is sitting in your warehouse. That is the unit price, plus freight, plus duty, plus any payment fee, divided by the pieces you can actually sell. A supplier offering free shipping on minimum orders can beat a supplier with a lower unit price and a separate freight charge — on this site, orders that reach the MOQ ship free to major markets, so the quoted price and the delivered price are the same number.
Do the mixed-batch arithmetic
If you are testing a market rather than filling a container, compare the cost of a mixed order against the cost of three separate minimum orders. Mixing models and categories into one batch is the single biggest lever a first-time buyer has, because it spreads the freight and the payment fee across more sellable units. It is also the fastest way to find out which design actually sells before you commit to a large run of one model.
The sample-first workflow
Samples exist to answer three questions that no catalogue photo can: does the material feel like the grade you want to sell, does the fit actually grip the charging case, and does the finish survive a week in a pocket. Order samples of every model you are seriously considering, not just the cheapest one.
What a sample test should prove
Put the case on a charging case and open and close the lid fifty times. Check whether the silicone stretches out of shape, whether the lid gapes, and whether the surface marks when you scuff it with a fingernail. If the sample has printing, check the print edge under a bright light — a blurred edge shows up immediately on a retail shelf, and it will not improve at volume.
Write down what you tested
Keep a short record per model: sample date, material, thickness, fit verdict, and whether you would reorder. When your first bulk order arrives, compare it against that record. This is how buyers catch a supplier who switches material between the sample and the production run, which is one of the most common reasons a second order feels different from the first.
Red flags to avoid
Most bad sourcing decisions are visible weeks before the money leaves. Watch for a supplier who quotes a price without asking which model you want; who cannot state an MOQ per model; who answers a compliance question with a general company certificate; who refuses a sample; who quotes a price that is dramatically below every other supplier without explaining why; and who will not put the specification in writing. Any one of these is worth a second question. Two of them together are worth walking away.
The reverse is also true: a supplier who asks you for the charging case dimensions, who separates dispatch from transit, and who tells you which models carry a higher minimum is showing you their production process. That is what you are really buying when you buy wholesale.
Frequently asked questions
What is the minimum order for TWS earbud cases?
On this site the minimum is 20 pieces per model for most protective cases, with some models starting at 10. The minimum applies per model, not per order, so you can combine several designs into one batch.
Can I mix different models in one order?
Yes. Mixing models and categories in a single batch is the normal way to place a first order, and it counts towards the same minimum. You can see the range in headphones, earbuds and protective cases.
Do I have to pay for shipping?
Orders that reach the minimum order quantity ship free by air express to major markets. If you would rather use your own freight forwarder in China, we deliver to them in 3–5 business days and you arrange the export leg, which reduces the unit price further.
How long does delivery take?
Dispatch is 3–5 business days after the order is confirmed. Air express transit is typically 14–25 days depending on destination customs, and every order ships with a tracking number.
What payment methods do you accept?
PayPal, Stripe and T/T bank transfer. For a first order, PayPal or Stripe give you buyer protection while you are still measuring whether the product sells.
Can you put my logo on the cases?
Yes. Logo printing and custom packaging are both available, and the options are explained in OEM versus private label for 3C accessories.
Next step
Send us the charging case you are sourcing for, the models you want to test, and your target market. You will get tiered pricing, the MOQ per model and the shipping cost back, usually within one business day.
Get a quote for your first order
Tell us the models you are sourcing and your target market — you will get the MOQ per model, tiered pricing and the shipping cost back, usually within one business day.