A Laos IoT buyer crossing a 2520 high-Q chip inductor to Walsin should check the tolerance letter. In Walsin’s export all 26 WFI2520 parts ending in K print plus or minus 5 percent, while WFI2012 and WLFW2520 K parts print plus or minus 10 percent. None is on our 23 September 2026 shelf.
Venatech Limited, an authorised Walsin distributor in Hong Kong, holds the Walsin Technology (Walsin) inductor parametric export, file Walsin_Inductor_ALL.xlsx: 5,411 rows, 5,410 real part numbers once a QA test row is removed. This post is for a procurement or design engineer at an electronics assembler in Laos who wants Walsin candidates for a 2012 or 2520 high-Q chip inductor with every difference stated. Every Walsin part number below is real, every count is ours, and the one news fact is dated and sourced (fetched 2 November 2026).
What did Laos start to change at its borders?
The Laotian Times reported on 22 October 2026 that Laos has launched the Second Lao PDR Competitiveness and Trade Project, a five million dollar programme running to March 2029 that aims to digitise 86 import and export permits and cut average border cargo clearance to around two hours. It was launched on 20 October.
The report adds that the project seeks to bring 25 percent of business registrations online and to use the Lao-China Railway and inland dry ports to speed goods movement, and it notes Laos is planned to graduate from least-developed-country status on 24 November 2026. It names no funder, no border crossing and no component. We draw no conclusion about any Lao company’s imports. We have no relationship with the project or the newspaper.
| Point | What the source says | Source date | Match / mismatch |
|---|---|---|---|
| Programme | Second Lao PDR Competitiveness and Trade Project, to March 2029 | Laotian Times, 22 October 2026 | Match for context only |
| Permits | 86 import and export permit types to be digitised | Laotian Times, 22 October 2026 | Match for context only |
| Border clearance | Average cargo clearance cut to around two hours | Laotian Times, 22 October 2026 | Match for context only |
| Electronic components | Not mentioned | Laotian Times, 22 October 2026 | Mismatch with any component claim |
How many Walsin WFI2520 parts print the wrong tolerance for their suffix?
We parsed all 197 rows of the WLFW/WFI series: 109 WFI and 88 WLFW, in 2012 and 2520 sizes. They collapse to 145 distinct electrical rows, and 26 carry three part numbers: a WFI J, a WFI K and a WLFW J. The reason is that all 26 WFI2520 K parts print plus or minus 5 percent, the same as their J twins.
In the 2012 size the K parts print plus or minus 10 percent (28 of 28), and every one of the 26 WLFW2520Z0K parts prints plus or minus 10 percent. So the WFI2520 K column disagrees with its own 2012 size and with the WLFW K twin. We have not seen this counted anywhere. One WFI2520 row, WFI2520FSR10H, prints plus or minus 3 percent, so the H suffix at least behaves.
| Part | Size, inductance, Q, current | Tolerance printed | Match / mismatch |
|---|---|---|---|
WFI2520FS47NJ |
2520, 47 nH, Q 50, 650 mA | plus or minus 5 percent | Match with its WLFW J twin WLFW2520Z0J47NPB |
WFI2520FS47NK |
2520, 47 nH, Q 50, 650 mA | plus or minus 5 percent | Mismatch: K suffix, but WLFW2520Z0K47NPB prints 10 percent |
WFI2012FS78NJ |
2012, 78 nH, 2 A | plus or minus 5 percent | Match with WLFW2012Z0J78NPB; Q 0 in the WFI row against Q 19 in the WLFW row |
WFI2012FS78NK |
2012, 78 nH, 2 A | plus or minus 10 percent | Match with WLFW2012Z0K78NPB on tolerance |
WFI2520FSR10K |
2520, 100 nH, Q 50, 700 mA | plus or minus 5 percent | Mismatch: the same K-suffix disagreement at a second inductance |
Your incumbent part goes in a sixth column on your own copy; we do not name one.
What does the export not tell you about these inductors?
The export prints a tolerance for all 197 rows but cannot tell you which of the 52 K-suffix rows at 2520 is right, and 0 of our 28 datasheets cover an inductor. Either the K suffix at 2520 is a plus or minus 5 percent part or the column is wrong. We cannot resolve it without Walsin’s sheet.
The WFI2012 rows also print a Q minimum of 0 where the WLFW2012 twin prints 19, which reads as a missing value rather than a difference in the part. A buyer who specifies a tight tolerance for a matching network should ask Walsin to confirm the family sheet before accepting a K part. We do not say which name is preferred for new designs, and we hold no packaging, temperature range or resonant curve for either family.
Why buyers in Laos choose Venatech
Buyers in Laos choose Venatech because we are an authorised Walsin Technology distributor working from Hong Kong, we supply small lots, and we show you every mismatch as well as the match. For this one family we counted 197 rows down to 145 electrical rows, found the 26 K-suffix parts whose tolerance column disagrees with their own size, and put them in the table. A buyer can then ask Walsin the right question before a lot is ordered.
The VenaMatch cross-reference tool decodes 18 manufacturers’ part numbers and covers 800,000+ crossable parts, with every difference from your original stated. The BOM page takes up to 500 part numbers. We say what we do not hold: we hold neither ISO 9001 nor IATF 16949, and we hold no inductor datasheets. Lot and date-code traceability and a certificate of conformity per shipment are available on request. Ask, and we will tell you plainly what we can and cannot supply.
What will we not tell you about Laos?
Anything about Lao customs, certification, import permits or the trade project. We hold no office, entity or stock in Laos; our locations are Hong Kong, Shenzhen, Singapore and Jiangmen, with Chengdu in preparation. We state no duty rate, transit time or conformity requirement, give no legal or customs advice, and make no statement about clearance times; confirm with your compliance team. We also make no statement about any lock or sensor product.
How Venatech helps
Paste the incumbent inductor number into the free cross-reference tool, which decodes 18 manufacturers’ part numbers across 800,000+ crossable parts and lists Walsin candidates with match and mismatch fields, or upload the list to the BOM checker, up to 500 part numbers. The Hong Kong ready-stock list is a dated snapshot, 23 September 2026, never live-synced; it holds none of the 197 rows above. Walsin is the only line we are authorised for; Stackpole and Viking are lines we supply. We work from Hong Kong, in small lots, and you can request a quote through the site. Worked example from our export: WFI2520FS47NJ and WLFW2520Z0J47NPB agree on 47 nH, Q 50 and 650 mA. Our post on inductor tolerance codes explains the letters, multilayer versus wirewound inductors covers the families, and the inductor range lists them. Qualification stays with you.
The short version
Check the tolerance letter against the column. In Walsin’s WFI and WLFW export, 26 of 26 WFI2520 K parts print plus or minus 5 percent while every other K part in the series prints plus or minus 10 percent, and 26 electrical rows carry three names. None is on the 23 September 2026 shelf. Confirm against the datasheet and qualify in your own circuit.
Send us one high-Q inductor line from your bill of materials and we will return the Walsin candidates with every difference stated. Which tolerance does your drawing actually require?
Sources
Fetched 2 November 2026. The Laos news comes from this page; the part data, counts and stock position come from our own Walsin exports and stock list.
- The Laotian Times, “Laos Targets Faster Border Checks in Five Million Dollar Trade Project”, 22 October 2026: https://laotiantimes.com/2026/10/22/laos-targets-faster-border-checks-in-u%73d-5-million-trade-project/
Frequently asked questions
What did Laos launch on 20 October 2026?
The Laotian Times reported the Second Lao PDR Competitiveness and Trade Project, a five million dollar programme to March 2029 that aims to digitise 86 import and export permits and cut average border clearance to around two hours. It names no components.
How many Walsin WFI2520 K parts disagree with their suffix?
All 26. Each WFI2520 part ending in K prints plus or minus 5 percent, the same as its J twin, while the 28 WFI2012 K parts and the 26 WLFW2520 K parts print plus or minus 10 percent.
Which tolerance should I assume for a WFI2520 K part?
Do not assume. Either the column or the suffix is wrong, and we hold no Walsin inductor datasheet to settle it. Ask Walsin to confirm the family sheet and specify the tolerance in plain numbers on your drawing.
Are the WFI and WLFW parts the same electrical part?
On the fields in the export, yes for 26 rows: size, thickness, inductance, tolerance, Q minimum, resonant frequency, resistance and current agree across three names. The WFI2012 rows print a Q minimum of 0 where WLFW prints 19, which reads as a missing value.
Are any of these inductors on your shelf?
None of the 197 rows is on our 23 September 2026 Hong Kong ready-stock snapshot, which is dated and not live. Check the ready-stock page, or ask us to quote a lot, which we can do in small quantities from Hong Kong.
Do you ship to Laos or state its import rules?
We ship from Hong Kong and state no duty, customs, certification or transit information for Laos. We hold no office or stock there and give no legal or customs advice; confirm with your compliance team. You can request a quote through the site.