- An advanced grindstone used in the finish machining of weapon parts. Can be used for a variety of upgrades and the synthesis of D32 Steel.
- Compared to normal Grindstone, this tool has an even more stable structure. It is highly non-reactive.
The second of the Grindstone-type upgrade materials, Grindstone Pentahydrate is similar but much more stable and non-reactive, thus making it more useful and essential for Operator skill Mastery training and the Elite 2 promotion of 5★ and 6★ Operators.
Due to its stability, the Grindstone Pentahydrate is an important material for the synthesis of D32 Steel.
Grindstone Pentahydrates are available in:
|300||4||Level 3 Workshop|
- Pentahydrate is a suffix used for chemical compounds with five water molecules bound to it.
- Grindstone – T3 counterpart