SILVERHOOK Silicone Grease Water Proof - 500g Tin — Mo-kit | Workshop Consumables
Silicone grease can help to seal the cap and keep the nib wet for the next time you write (so far so good). More info in the comment section. : r/fountainpens
Grease
SILVERHOOK Silicone Grease Tub 500g : Amazon.co.uk: Automotive