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STOCK-BASED COMPENSATION PLANS (Tables) | 9 Months Ended
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Sep. 30, 2025
STOCK-BASED COMPENSATION PLANS |
Schedule of outstanding and exercisable number of options | ​
​ | ​ | ​ | ​ | ​
​ |  | ​ |  | ​
​ | ​ | ​ | ​ | ​
​ | ​ | Outstanding Number of Options | ​ | Exercisable Number of Options
​ | ​ | (in thousands) | ​ | (in thousands)
Plan Category |  |  |  |
2005 Stock Option Plan |  | 1 | ​ | 1
2017 Stock Option Plan |  | 328 | ​ | 328
Total |  | 329 | ​ | 329
Schedule of stock-based compensation expenses recorded in the condensed consolidated statements of operations | The following summarizes stock-based compensation expenses recorded in the condensed consolidated statements of income (in thousands): ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | For the Three Months Ended September 30, |  | For the Nine Months Ended September 30,
​ |  | 2025 |  | 2024 |  | 2025 |  | 2024
Costs of revenue - devices and supplies | ​ | $ | 8 | ​ | $ | 10 | ​ | $ | 29 | ​ | $ | 27
Sales and marketing | ​ |  | (31) | ​ |  | 125 | ​ |  | 125 | ​ |  | 492
General and administrative | ​ | ​ | 340 | ​ | ​ | 635 | ​ | ​ | 1,299 | ​ | ​ | 1,826
Total stock-based compensation expense | ​ | $ | 317 | ​ | $ | 770 | ​ | $ | 1,453 | ​ | $ | 2,345
Schedule of stock option activity under all equity compensation plans | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | Weighted- | ​ | ​ | ​
​ | ​ | ​ | ​ | Weighted- | ​ | Average | ​ | Aggregate
​ | ​ | Number of | ​ | Average | ​ | Remaining | ​ | Intrinsic
​ | ​ | Shares | ​ | Exercise | ​ | Contractual | ​ | Value
​ |  | (in thousands) |  | Price |  | Term (Years) |  | (in thousands)
Outstanding at December 31, 2024 |  | 335 | ​ | $ | 1.78 | ​ | 3.09 | ​ | $ | 2,086
Granted |  | — | ​ | ​ | — | ​ | — | ​ | ​ | —
Forfeited | ​ | (4) | ​ | ​ | 3.13 | ​ | — | ​ | ​ | —
Exercised |  | (2) | ​ | ​ | 3.36 | ​ | — | ​ | ​ | —
Outstanding and exercisable at September 30, 2025 |  | 329 | ​ | $ | 1.76 | ​ | 2.37 | ​ | $ | 146
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Schedule of restricted stock award activity under all equity compensation plans | ​
​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Number of | ​ | ​
​ | ​ | Shares |  | Weighted Average
​ |  | (in thousands) |  | Grant Date Fair Value
Outstanding at December 31, 2024 | ​ | 499 | ​ | $ | 10.28
Granted | ​ | 368 | ​ | ​ | 2.47
Forfeited | ​ | (109) | ​ | ​ | 7.81
Vested | ​ | (211) | ​ | ​ | 9.63
Outstanding at September 30, 2025 |  | 547 | ​ | $ | 5.77
​ | ​ | ​ | ​ | ​ | ​

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