Cobalt Blue – Subtle, but Distinct Sometimes you don’t need neon yellow or toxic green to stand out. This Spyderco UK Penknife comes in rich Cobalt Blue G10 – subtle enough for everyday carry, yet distinctive enough that you’ll enjoy pulling it out of your pocket. The UKPK was originally designed to comply with stricter European knife laws. It opens one-handed via the signature Spyderco Round Hole, but the blade does not lock. Instead, it relies on a strong back spring – a classic slipjoint construction. Functional, straightforward, and perfectly suited for daily use. The approximately 7.5 cm blade in this version is made from SPY27, Spyderco’s proprietary steel. It offers a well-balanced mix of edge retention, corrosion resistance, and ease of sharpening – exactly what you want in real-world use. The high full flat grind ensures clean, efficient cutting performance rather than brute-force wedging. The G10 handle scales make the knife slightly heavier than the FRN version, but they also provide a noticeably more solid, premium feel in hand. More substance, without becoming bulky.