# K961489: Elecsys FT4 Assay

- Pathway: 510(k) (Traditional)
- Applicant: Boehringer Mannheim Corp.
- Decided: Jun 11, 1996 after 54 days
- Product code: CEC (Radioimmunoassay, Free Thyroxine)
- Device class: 2
- Regulation: 21 CFR 862.1695
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 1 generation back to K900883 (1990). 1 ancestor in all.
5 later devices descend from it; 3 cite it directly.
0 of 7 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K900883: Enzymun Test (R) FT4 (Free Thyroxine), Boehringer Mannheim Corp. (1990) Summary page 1.

## Most influential descendants
- K131244: Elecsys FT4 II Assay, Elecsys FT4 II Calset (2014), 2 descendants of its own
- K220456: Elecsys FT4 IV (2023), 0 descendants of its own
- K181233: Elecsys FT4 III (2018), 0 descendants of its own
- K132058: Vidas FT4 (2015), 0 descendants of its own
- K121951: Liaison FT4 Liaison Control Thyroid 1 Liaison Control Thyroid 2 Liaison Control Thyroid 3 (2013), 0 descendants of its own

## Indications for use
Immunoassay for the in vitro quantitative determination of free thyroxine in human serum and plasma.

Source page: https://510kreport.com/device/K961489
Methodology: https://510kreport.com/methodology