F4Phantom replied:

home made is usually fabricated steel tube or PVC. Steel is much more professional but cannot flex, and if you need a snorkel you probably hit areas where flex could be good in tight spaces. I made my own which could be classed somewhere in between. I used large diameter flexable tube for the whole length all the way into the engine with a ricey pod filter in the way. I put a bit of pvc pipe to keep the flex tube straight where it gets bolted along the windwscreen. The finnished idea is that you have a clean look with no joining, flexable, easy to make. It still looks home made but I use it to keep water out of the engine not win awards for the most brand names on one car.