This section is enabled and filled in the CLASS observation header if the FITS card OBS_MODE contains the string FSwitch and if a non-null LO throw value is found in the FITS data.
| CLASS | Type | Value | Default |
| nphas | I*4 | 2 | |
| swmod | I*4 | Metacard isFolded (T/F), translated to CLASS internal code | code for False |
| decal[1] | R*8 | 0.d0 | |
| duree[1] | R*4 | 1.0 | |
| poids[1] | R*4 | +0.5 | |
| decal[2] | R*8 | Column LoThrow else lothrow (level 2.0), or | |
| Metacard LoThrow else loThrow (level 2.5) | |||
| duree[2] | R*4 | 1.0 | |
| poids[2] | R*4 | -0.5 |