Cleared Special

K201131 - firefly T-2 (FDA 510(k) Clearance)

Class II Physical Medicine device cleared through the Special 510(k) pathway - typically does not require clinical trials.

Download Printable Device Report (PDF)
Optimized for regulatory review, auditing and printing
May 2020
Decision
30d
Days
Class 2
Risk

K201131 is an FDA 510(k) clearance for the firefly T-2. Classified as Stimulator, Muscle, Powered, For Muscle Conditioning (product code NGX), Class II - Special Controls.

Submitted by Firstkind Limited (High Wycombe, GB). The FDA issued a Cleared decision on May 28, 2020 after a review of 30 days - a notably fast clearance cycle.

This device falls under the Physical Medicine FDA review panel, regulated under 21 CFR 890.5850 - the FDA physical medicine device framework. As a Special 510(k), this submission covers a manufacturer modification to an existing cleared device rather than a new device introduction.

Device pattern: Iterative device modification. Low regulatory complexity profile. This Special 510(k) clearance confirms that the manufacturer's modifications remained within the established regulatory envelope of the original cleared device.

View all Firstkind Limited devices

Submission Details

510(k) Number K201131 FDA.gov
FDA Decision Cleared Substantially Equivalent - Traditional 510(k) (SESE)
Date Received April 28, 2020
Decision Date May 28, 2020
Days to Decision 30 days
Submission Type Special
Review Panel Physical Medicine (PM)
Summary Summary PDF
Third-party Review No - reviewed directly by FDA
Regulatory Context
Review time vs. panel average
85d faster than avg
Panel avg: 115d · This submission: 30d
Pathway characteristics
Modification to existing cleared device.

Device Classification

Product Code NGX Stimulator, Muscle, Powered, For Muscle Conditioning
Device Class Class 2 - Special Controls
CFR Regulation 21 CFR 890.5850
Definition A Powered Muscle Stimulator For Muscle Conditioning Is A Device Used For Other Than Medical Purposes To Apply An Electrical Current To Electrodes On A Person's Skin To Temporarily Affect The Stimulated Muscle's Contractile Properties, Force Output, And/or Fatigue Resistance. Unlike The Classified Powered Muscle Stimulator Devices Intended For Use In Physical Medicine And Rehabilitation, This Device Is Not Intended For Use In Patients With Medical Conditions And Is Intended Only For Muscle Conditioning Purposes.
What this classification means

Class II devices require demonstration of substantial equivalence to a legally marketed predicate device. This pathway does not require clinical trials - it relies on engineering equivalence and performance data. Most Physical Medicine devices follow this clearance model.

Regulatory Peers - NGX Stimulator, Muscle, Powered, For Muscle Conditioning

All 161
Devices cleared under the same product code (NGX) and FDA review panel - the closest regulatory comparables to K201131.
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