All photos below © Cory.

North Korean stickgrenade.
Click on the image to see some more.

F1 defensive grenade :

Slightly different fromthe Russian F1.
The body has a small carrying lug.

The grenade seems to be fitted with a plastic adapter to fit the fuze.

RGD offensive grenade :

No difference visible between this grenade and the Russian RGD-5.

RKG antitank grenade :

Exactly the same grenade as the Russian RKG-3.

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"Rectangular Fragmentation Grenade"

There seemed to have been at least two rectangular-shaped grenades used in North Korean army.
The one on the right seems to be much slimmer then the one shown below (Japanese Police Museum)

Photos © Joe.

The following information came from US manual FM 3-23.30 , 2000-edition :

Type : Fragmentation
Weight : 370 gram
Body Material : Sheet steel with about 1,300 steel balls in a cavity between the outer wall and the explosive filler
Fuze : Striker release
Fuze Delay : 3.2 to 4.2 seconds
Filler : Composition B, 55 gram
Effective Casualty Radius : 20 meter

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"Canister hand grenade"

Photo right provided by Franz.

Photo and information below thanks to Joe.
This photo was taken at the Korean War Museum, where this grenade is designated as "Canister Hand Grenade".
It was used in the 1960's by North Korean Special Forces.

Total length :
Diameter : 52mm
Weight : 553gram

The following information came from US manual FM 3-23.30 , 2000-edition :

Type : Fragmentation
Weight : 600 grams
Body Material : Cast aluminum body with 140 to 150 cast iron balls embedded in it
Fuze : Striker release
Fuze Delay : 3.2 to 4.2 seconds
Filler : TNT, 60 gram
Effective Casualty Radius : 20 meter
NOTE : A variation of this grenade has a plastic body

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