Ordtech OMI-IV-7 and OMI-IV-19 electromechanical intervalometer for 2.75 inch Rocket Launchers (LAU-xxx series)is the only known, currently in production intervalometer which meets or exceeds standard MIL-S-8537 equivalent to 356AS172-1 & -2
| Ordtech P/N | Application | Interchangeable P/N | Interchangeable NSN | Usage |
| OMI-IV-7 | 7-tube launchers 2.75″ | 356AS172-1 | 1340-00-157-5917 | Re-Usable 50+ firings |
| OMI-IV-19-M | 19-tube launchers 2.75″ | 356AS172-2 | 1340-00-390-3885 | Re-Usable 50+ firings |
| OMI-IV-19-S | 19-tube launchers 2.75″ | 177410-001 | 1340-00-760-4226 | Single use Disposable |