Drawings done in this or that sketchbook. I don't use a straightedge in this situation, but do hold my breath for uncomfortable durations.
Airplane drawing B [Dallas/Ft. Worth International Airport, Texas>>Narita International Airport, Japan] \\\ red+black+blue 'Pilot Razor Point II' pens.
Airplane drawing B [Narita International Airport, Japan>>O'Hare International Airport, Chicago] \\\ .25-.4mm ink pen, obtained from MUJI store near ??????, Seoul, South Korea.
taupe\\\.15-.5 Prismacolor pen
deep-sea Fishing\\\Prismacolor pen
blue bic ball-point pen
Napkin sketch\\\Mexico
Napkin sketch\\\cafe el Silo, Tacubaya, Mexico City, Mexico\\\bic ball-point pen
tiny refractions\\\Barrel-fed white charcoal on black
somekindacarapace\\\2H staedler graphite
extronaut\\\barrel-fed white charcoal on black
Ruptures\\\Prismacolor pen
strikes\\\red 'le pen' pen
Insomniac drawing\\\graphite powder+red staedler lead