In body form, this smoke grenade looks the same as the PLMP7B, which is a teargas grenade.
It was also in use in Switzerland.

Length : 164mm
Diameter : 51mm
Weight : 317g
Filling : 7 smoke pellets with plastic case: 239g
Fuze : Bouchon Retard 2.5sec (in Switzerland)

Photos © W. Schumann.