My job involves writing things down and drawing pictures. So a pencil case is a requirement, well maybe not a requirement, I'm the only person on my team with a pencil case, but the rest of em don't know what they're missing out on.
My case of choice for everyday work use is this Lihit triple. I've had this one for years, it's a bit grubby, but still works a treat. The three layers give you plenty of storage for all your pens.
First layer
I keep coloured felt tips and fine liners in the first layer. The felt tips are Pentel Sign pens, they've got a slightly soft prush style tip that do fairly fine strokes and with a little pressure thicker ones. The fine liners are Pigma microns, various tip widths from super skinny to skinny. They're all filled with black pigment ink, so they don't run, dry quickly and are waterproof when dry. There's also a sharpie in there!
Middle layer under the flap
The next layer has a flap over sleeve, on the bottom there's an fine eraser and spare tips a fine rollerball and a purple fineliner. On the other side is a set of Bic medium fine line felt tips. They're good as highlighters and good for small areas of colour.
Middle layer over the flap
The other side houses a couple of mechanical pencils, roller balls, a fineliner and traditional pencil. The bottom holds my Lamy fountain pens. There's one with blue ink and one with black. Two fountain pens in a work pencil case is probably a bit much... I like fountain pens!
Tools layer
The final layer holds tools. There's a straight edge and a ruler, a pair of scissors, a USB lead and a tiny folding multitool. In the nets on the other side there's a spare ink cartridge, an eraser, USB memory stick, pencil sharpener. The bottom one is a bag of mechanical pencil leads - the mechanical pencils are a few different diameters and there's some coloured leads in there too.
