X0306 4 2022-06-15 false 0001555279 908 Devices Inc. MASS 0001237190 ELOI FENEL M C/O 908 DEVICES INC. 645 SUMMER STREET BOSTON MA 02210 true false false false Common Stock, par value $0.001 2022-06-15 4 M false 1379.00 A 1887.00 D Restricted Stock Unit 2022-06-15 4 M false 1379.00 0.00 D Common Stock, par value $0.001 1379.00 0.00 D Restricted Stock Unit 2022-06-16 4 A false 4771.00 0.00 A Common Stock, par value $0.001 4771.00 4771.00 D Stock Option (option to buy) 14.15 2022-06-16 4 A false 7970.00 0.00 A 2032-06-16 Common Stock, par value $0.001 7970.00 7970.00 D Each Restricted Stock Unit ("RSU") represents a contingent right to receive one share of Common Stock, par value $0.001, when vested. The RSUs became fully vested on June 15, 2022, the day prior to the 2022 Annual Meeting of the Stockholders of 908 Devices Inc. The RSUs have no expiration date. The RSUs become fully vested on June 16, 2023 or the day prior to the 2023 Annual Meeting of the Stockholders of 908 Devices Inc., whichever occurs first, subject to the reporting person's continued service through the applicable vesting date, provided that, if the reporting person terminates their service for any reason, then a prorated number of RSUs will vest. The RSUs have no expiration date. The shares underlying the option become vested and exercisable in substantially equal monthly installments over the 12 months following June 16, 2022, subject to the reporting person's continued service through the applicable vesting date. /s/ Michael S. Turner, as Attorney-in-Fact 2022-06-17