# K121719: SM Tens & PMS

- Pathway: 510(k) (Traditional)
- Applicant: Hong Qiangxing (Shenzhen) Electronics Limited
- Decided: May 10, 2013 after 333 days
- Product code: NGX (Stimulator, Muscle, Powered, For Muscle Conditioning)
- Device class: 2
- Regulation: 21 CFR 890.5850
- Recalls of this device: none
- Data: FDA decisions to Oct 25, 2026; recalls to Oct 12, 2026

## Lineage
Longest line of descent: 4 generations back to K940301 (1994). 6 ancestors in all.
30 later devices descend from it; 3 cite it directly.
0 of 37 devices in its family (counting itself) have a Class I recall.

## Predicates on the family tree (from the FDA summary)
- K102598: HI-Dow-XP, Hi-Dow International, Inc. (2011) Summary page 2.

## Most influential descendants
- K133929: Health Expert Elctronic Stimulator (2014), 26 descendants of its own
- K190783: Health Expert Electronic Stimulator (model: AST-300L) (2020), 6 descendants of its own
- K172897: Neck Care Therapy, Model: SYK 509B (2018), 3 descendants of its own
- K191982: Low-Frequency Multi-function Physiotherapy Instrument (Model: KTR-2230, KTR-2220, KTR-2210, KTR-2231, KTR-2221, KTR-2211, KTR-2232, KTR-2222, KTR-2212) (2020), 2 descendants of its own
- K163611: Pain Therapy Device (2017), 2 descendants of its own

## Indications for use
To be used for temporary relief of pain associated with sore and aching muscles in the shoulder, waist, back, neck, upper extremities (arm), and lower extremities (leg) due to strain from exercise or normal household work activities. It is intended to be used to stimulate healthy muscles in order to improve and facilitate muscle performance.

Source page: https://510kreport.com/device/K121719
Methodology: https://510kreport.com/methodology