510(k) · Cleared
ClearedOB1 Obstetrical Doppler
Data to Oct 25, 2026 (FDA decisions) Oct 12, 2026 (recalls) Sep 30, 2026 (MAUDE) refreshed weekly
D. E. Hokanson, Inc. · KNG Monitor, Ultrasonic, Fetal
Cleared on Dec 9, 2003 as substantially equivalent to K930200 (Huntleigh Healthcare, Inc., 1994) and 2 other predicates after a 70-day review. Its family tree reaches back 3 generations to 1994.
- Decided
- Dec 9, 2003
- Review
- 70 days
- Class
- Class II
- Product code
- KNG
- Recalls
- None
- Predicates
- 3
Its longest line of descent runs back 3 generations to K930200 (1994). No later device cites it as a predicate yet.
- Root · 3 generations backK930200 Multi Dopplex II / Fetal Dopplex IIHuntleigh Healthcare, Inc. · 1994
- 2 generations backK991441 Cadence Doppler Ultrasound SystemMedasonics, Inc. · 1999
- 1 generation backK024197 Lifedop DopplerSummit Doppler Systems, Inc. · 2003 · Recalled
- This deviceK033156 OB1 Obstetrical DopplerD. E. Hokanson, Inc. · 2003
View FIG. 1 as a table
Line of descent and top descendants
| Generation | Number | Device | Applicant | Decided | Recalls |
|---|---|---|---|---|---|
| −3 | K930200 | Multi Dopplex II / Fetal Dopplex II | Huntleigh Healthcare, Inc. | 1994 | — |
| −2 | K991441 | Cadence Doppler Ultrasound System | Medasonics, Inc. | 1999 | — |
| −1 | K024197 | Lifedop Doppler | Summit Doppler Systems, Inc. | 2003 | 1 |
| 0 (this device) | K033156 | OB1 Obstetrical Doppler | D. E. Hokanson, Inc. | 2003 | — |
Sources: FDA 510(k) database (decision fields), the FDA summary (predicates and indications), FDA recall and enforcement reports, and MAUDE; processed by 510(k) Report. Verify on FDA.gov · Methodology and accuracy.
Planning a device in KNG? A 510(k) Report weighs predicate choices, recall history and review times for a new device like this one.
Top candidate predicates for a new KNG device
- #1 K252669 Fetal Doppler U8-25, U9-25score 13.0 · 9 generations · no Class I recall
- #2 Held for the reportin the report
- #3 Held for the reportin the report
What was it cleared against? (3)
Devices the submitter claimed this one is substantially equivalent to (*), and reference devices cited for a specific test or feature (†), as written in the FDA summary.
| Type | Number | Device | Decided |
|---|---|---|---|
| * | K930200 | Multi Dopplex II / Fetal Dopplex IISummary page 1…or four seconds. Substantial Equivalence Huntleigh Technologies, Manalapan, NJ to Predicate Devices Dopplex II Pocket Doppler, K930200, cleared 6/24/94 Medasonics Incorporated, Newark, CA Cadance Doppler Ul… | 1994 |
| * | K991441 | Cadence Doppler Ultrasound SystemSummary page 1…Pocket Doppler, K930200, cleared 6/24/94 Medasonics Incorporated, Newark, CA Cadance Doppler Ultrasound System, K991441, cleared 12/28/99 Summit Doppler Systems, Inc., Arvada, CO… | 1999 |
| * | K024197 | Lifedop DopplerSummary page 1…12/28/99 Summit Doppler Systems, Inc., Arvada, CO LifeDop Doppler Ultrasound System, K024197, cleared 1/03/03 Technology Summary Doppler ultrasound technology in the OB1 is substantia… | 2003 |
What descends from it?
No later submission names this one as a predicate yet.
Has anything in its family been recalled? (0 Class I)
No FDA recall names this device.
No ancestor or descendant has a Class I recall.
What does this lineage say?
- The line of descent spans 9 years and passes through 4 companies; a new generation was cleared every 3.0 years on median.
- 1 of the 3 ancestors has a recall of any class.
- 4 other devices also cite its predicate K930200.
How does its category compare?
All KNG devicesKNG Monitor, Ultrasonic, Fetal: FDA decisions, review times, recalls and adverse event reports over 20 years.
FDA decisions per year · KNG
1in 2025
2026 to Oct 25, outlined.
Median 510(k) review, days · KNG
202in 2019
Receipt to decision; years with fewer than 3 clearances left blank.
Recalls per year · KNG
No recall names KNG since 2007.
Adverse event reports per year · KNG
1in 2025
MAUDE reports naming product code KNG, not matched to any one device; reports are not rates.
View these four charts as a table
| Year | Decisions | Median 510(k) review, days | Recalls (Class I) | MAUDE reports |
|---|---|---|---|---|
| 2007 | 0 | — | 0 | 0 |
| 2008 | 1 | — | 0 | 2 |
| 2009 | 3 | 181 | 0 | 0 |
| 2010 | 2 | — | 0 | 0 |
| 2011 | 5 | 57 | 0 | 0 |
| 2012 | 0 | — | 0 | 0 |
| 2013 | 0 | — | 0 | 1 |
| 2014 | 1 | — | 0 | 1 |
| 2015 | 1 | — | 0 | 0 |
| 2016 | 1 | — | 0 | 0 |
| 2017 | 0 | — | 0 | 3 |
| 2018 | 3 | 154 | 0 | 8 |
| 2019 | 3 | 202 | 0 | 1 |
| 2020 | 0 | — | 0 | 2 |
| 2021 | 1 | — | 0 | 1 |
| 2022 | 2 | — | 0 | 0 |
| 2023 | 0 | — | 0 | 2 |
| 2024 | 2 | — | 0 | 3 |
| 2025 | 1 | — | 0 | 1 |
| 2026 | 1 | — | 0 | — |
What is it indicated for?
This product will be used to detect fetal heartbeats to help determine fetal viability.
Indications for use as stated in the FDA summary.
https://510kreport.com/device/K033156 · printed Nov 6, 2026
Cite this page
510(k) Report. “K033156: OB1 Obstetrical Doppler.” Lineage record from FDA 510(k) data and the FDA summary. Updated Nov 3, 2026. Accessed Nov 6, 2026. https://510kreport.com/device/K033156
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Record history
- FDA decision record loaded May 2, 2026
- Summary read Oct 13, 2026 (extraction version 9eaa42aa01ed)
- Lineage and recalls computed Nov 3, 2026
- Page last updated Nov 3, 2026