Progenix Select Stim

The Progenix Select Stim is a portable, battery-powered two-channel transcutaneous electrical nerve stimulator (TENS) device designed for over-the-counter use to provide temporary relief of pain associated with sore and aching muscles in the shoulder, waist, back, neck, upper and lower extremities, abdomen, and bottom due to strain from exercise or household work. The device consists of a stimulator unit, two lead wires, and four skin electrode pads, offering 10 preset TENS treatment programs in four operational modes: Conventional TENS (Continuous), Burst Mode, Modulation mode, and HAN TENS.

The Progenix Select Stim uses a single 9V battery (versus the predicate's 3×AAA batteries providing 4.5V), has lower maximum output voltage and current specifications (40-145V at varying impedances, 19-80mA), narrower pulse width range (50-200μs versus 50-450μs), and narrower frequency range (2-100 Hz versus 1-150 Hz). Both devices are two-channel, biphasic rectangular waveform stimulators with software/microprocessor control, automatic safety features, and comply with IEC 60601 series standards. The electrode pads are 50×50mm self-adhesive biocompatible patches.

IEC 60601-1 (general safety and essential performance), IEC 60601-1-2 (electromagnetic compatibility), IEC 60601-1-6 (usability), IEC 60601-1-11 (home healthcare environment), IEC 60601-2-10 (nerve and muscle stimulator requirements), IEC 62304 (software lifecycle), ISO 10993-5 (cytotoxicity), and ISO 10993-10 (irritation and skin sensitization) for electrode biocompatibility.

Substantial equivalence is established through identical intended use (OTC pain relief for the same body areas), identical regulatory classification (Class II, 21 CFR 882.5890, product code NUH), and identical fundamental design (portable battery-powered two-channel biphasic TENS stimulator). While output specifications differ (lower voltage/current, narrower pulse width and frequency ranges), the submitter argues these differences enhance safety without compromising effectiveness, as the narrower parameters remain within the recognized range for therapeutic electrical nerve stimulation and the device meets all applicable safety standards. No differences in technological characteristics raise new safety or effectiveness questions.