THUNDER TIGER K-ROCK MT4 Stainless Steel Pillow Ball For Front Knuckle Arms - 4pc set - GPM KG007SF  [KG007SF]

THUNDER TIGER 6406-F : PD1916
NERO / FAZON : AR330364

Device major function & use:

Secure front knuckle hands

Stainless is stronger and corrosion resistance.

Identical to original

Also ideal for Arrma Nero, Fazon