The Splittermantel, or Splitterring was a smooth fragmentation sleeve for the M24/39 and later the M43 stick grenades, developed by the SS in 1942. The serrated type was a later development of the Wehrmacht.
As German stick grenades had only a thin steel casing surrounding the explosive charge, they relied principally on blast for effect.
The addition of a Splitterring to a standard stick grenade gave it greatly increased fragmentation ability.
The smooth sleeve stayed in place because of a tight fit, the serrated type was kept in place with three keepers around the base, and secured with a tension ring.
Both versions can be found marked and unmarked.
A thirt version is know to be fitted over the cylindrical NIPOLIT grenade.

Photos below © Miguel A.J.

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