OPUS 88 NIB DESIGN UPDATE:
Opus 88 has updated their nib design!
Please see the images below for a reference
of their newer, sleeker nibs:

It is an eyedropper-style fountain pen, so you would unscrew the front section on the pen, and then with that eyedropper that is included, you would fill the ink into the barrel of the pen, and then reattach it.

"Opus 88" is imprinted on the bottom of the cap.

It is not completely transparent, but a little opaque. Opus 88 Demonstrator fountain pen comes with a stainless steel German nib that has "Opus 88" engraved on it. The nib sizes: EF, F, M, B and Stub 1.5mm. With the color options of clear, red, grey, and orange.

Specifications
- Type: Fountain Pen
- Body Material: Resin
- Cap Type: Screw
- Filling Mechanism: Eyedropper
- Nib Material: Stainless Steel (Jowo #6)

Dimensions
- Capped Length: 5.75 in (146.05 mm)
- Posted Length: (cannot be posted)
- Length of Body: 4.50 in (114.30 mm)
- Length of Cap: 2.50 in (63.50 mm)
- φ Body: 0.57 in (14.48 mm)
- φ Cap: 0.63 in (16.00 mm)
- φ Grip: 0.5 in (12.70 mm)