Sailor fountain pen refill 0500

Product code
[Black 0.7mm]
：18-0500-220
[Red 0.7mm]
：18-0500-230
[Blue 0.7mm]
：18-0500-240
[Black 1.0mm]
：18-0500-620
JAN code
[Black 0.7mm]
：49-01680-28601-1
[Red 0.7mm]
：49-01680-28602-8
[Blue 0.7mm]
：49-01680-28603-5
[Black 1.0mm]
：49-01680-28604-2
Specifications
Font width: thin/bold
Tip: Stainless steel 0.7mm/1.0mm
Application: For oil-based ballpoint pens
Body size
φ5.5×95.5mm
Body weight
3.4g
package
paper box
Size: 15×15×100mm
Weight: 7.0g

How to replace and refill the core