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v3.22.1

Commitments and contingencies (Tables) | 12 Months Ended
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Dec. 31, 2021
Commitments and contingencies |
Schedule of rent expense | The Company utilizes leased facilities and operates equipment under non-cancelable operating leases through July 2030. Below is a table of key properties: ​
​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ | ​ |  | Lease
​ | ​ | Annual | ​ | Expiration
Location | ​ | Rent | ​ | Date
Auburn, Washington | ​ | $ | 36,000 |  | 4/2022
Baton Rouge, Louisiana | ​ | $ | 24,600 |  | Month to Month
Champaign, Illinois | ​ | $ | 654,000 |  | 12/2024
Champaign, Illinois (2nd location) | ​ | $ | 349,000 | ​ | 9/2026
Charlotte, North Carolina | ​ | $ | 31,000 |  | 5/2022
Escondido, California | ​ | $ | 219,000 |  | 6/2022
Hampstead, New Hampshire | ​ | $ | 33,000 |  | 8/2023
Long Beach, California | ​ | $ | 28,800 |  | 2/2024
Ontario, California | ​ | $ | 168,000 |  | 12/2024
Riverside, California | ​ | $ | 27,000 |  | Month to Month
Rantoul, Illinois | ​ | $ | 36,000 | ​ | Month to Month
Smyrna, Georgia | ​ | $ | 465,000 |  | 7/2030
Stony Point, New York | ​ | $ | 105,000 |  | 6/2022
Woodcliff Lake, New Jersey | ​ | $ | 158,000 | ​ | 8/2027
​

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