No5 or No23 ??

[spotter]

This is another from my own collection ..its a No5 or No23 practice grenade.Does anyone know which???
Originaly Painted white to indicate practice ,this was in relic condition with faint traces of the white paint remaining, the safety pin/ring are non original and the base plug is a replacement

 

[3in]

the only thing i know about the differents in no 5and 26 is the possibiletyto fire the grenade as a rifle grenade by a different base plug to adobt a rifle rod ore the round base plate.
according ian v. hogg the no 5 was remodelled for manufacturing convenience, with larger lugs for the saftypin, a flat steel lever a striker with a notch on one site only and a hexagonal base plug