If you are looking for the best all-metal EDC pen under $25 the Retro 51 Tornado ( http://amzn.to/2pyYMyB ) is worth a look. This rollerball is built like a tank and is very cool looking. It ranges from about $30 for the highly styled ones down to just $20 for the base stainless steel model ( http://amzn.to/2G0XP9f ). I bought the stealth (all black) model for $24.
More information: https://unsharpen.com/pen/retro-51-tornado/
One nice perk of this pen is that it includes rebranded Schmidt refills ( http://amzn.to/2pBIxkb ) which are quite good and save you the price of upgrading your refills after you buy the pen.
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