Weight: 4 lb.
Estimated Value: 12,000 gp
While holding this rod, you gain a bonus to spell attack rolls and to the saving throw DCs of your warlock spells. The bonus is determined by the rod's rarity.
In addition, you can regain 1 warlock spell slot as an action while holding the rod. You can’t use this property again until you finish a long rest.
Source: DMG p197