# K031733: Non-Contact Tonometer, Model NT-4000

- Pathway: 510(k) (Traditional)
- Applicant: Nidek, Inc.
- Decided: Dec 4, 2003 after 183 days
- Product code: HKX (Tonometer, Ac-Powered)
- Device class: 2
- Regulation: 21 CFR 886.1930
- 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 K913189 (1991). 1 ancestor in all.
No later device cites it as a predicate yet.
0 of 2 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K913189: Nidek Model NT-1000, Nidek, Inc. (1991) Summary page 1.

## Indications for use
The Nidek Model NT-4000 is a non-contact tonometer that is indicated for use in the measurement of intraocular pressure of the human eye.

Source page: https://510kreport.com/device/K031733
Methodology: https://510kreport.com/methodology