# K173690: Grass TWin

- Pathway: 510(k) (Special)
- Applicant: Natus Medical Incorporated Dba Excel-Tech Ltd. (Xltek)
- Decided: Mar 9, 2018 after 98 days
- Product code: OLV (Standard Polysomnograph With Electroencephalograph)
- Device class: 2
- Regulation: 21 CFR 882.1400
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 2 generations back to K870450 (1987). 2 ancestors in all.
No later device cites it as a predicate yet.
0 of 3 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K012976: Twin Plus, Grass-Telefactor Divison (2002) Summary page 4.

## Indications for use
This software is intended for use by qualified research and clinical professionals with specialized training in the use of EEG and PSG recording instrumentation for the digital recording, playback, and analysis of physiological signals. It is suitable for digital acquisition, display, comparison, analysis, and archiving of EEG potentials and other rapidly changing physiological parameters.

Source page: https://510kreport.com/device/K173690
Methodology: https://510kreport.com/methodology