X0508 4 2024-06-25 false 0001555279 908 Devices Inc. MASS 0002027457 Leonhart Michele M. C/O 908 DEVICES INC. 645 SUMMER STREET BOSTON MA 02210 true false false false false Restricted Stock Unit 2024-06-25 4 A false 19456.00 0.00 A Common Stock, par value $0.001 19456.00 19456.00 D Stock Option (option to buy) 5.14 2024-06-25 4 A false 26810.00 0.00 A 2034-06-25 Common Stock, par value $0.001 26810.00 26810.00 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 become vested in substantially equal annual installments over the 3 years following June 25, 2024, 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 36 months following June 25, 2024, subject to the reporting person's continued service through the applicable vesting date. /s/ Michael S. Turner, as Attorney-in-Fact 2024-06-26