TWSBI Fountain Pen Wrench - Plastic (Red)
This is the red plastic wrench that is compatible with the TWSBI Eco Fountain Pen. It is usually supplied in the pen box with all new Twsbi Eco pens. It is too wide to use with Twsbi Diamond 580, Diamond Mini and Classic, which require the metal wrench.
To use the wrench, wind the end cap so the piston goes all the way down to the writing end. This will create the gap that you need to fit the wrench in. Silicone grease available separately.