TUSA Blue Tang Dive Knife

At a glance

TUSA Blue Tang Dive Knife is a dive knife from Tusa, rated 4.3 out of 5 and placed 10 of 13 in our lights & cutting shortlist. Its defining number is weight: 7.2 oz (204 g). It scores hardest on build quality (85/100) and softest on comfort and fit (61/100). The clearest advantage divers report: sharp out of the box and holds edge well.

What the dive knife actually gives you

Where it wins and where it costs you

Full review: TUSA Blue Tang Dive Knife

The Tusa Blue Tang dive knife is a compact, purpose-built cutting tool designed for divers who want a dependable blade without the bulk of larger models. Named for the vivid reef fish that inspired its accent color, this knife pairs a durable stainless steel blade with an ergonomic, textured handle that stays secure even when wet gloves are involved. Its blade geometry typically includes both a sharpened edge and a serrated section, giving divers the versatility to slice through fishing line, kelp, or tangled rope with equal ease. The blue detailing on the handle not only nods to the product's namesake but also improves visibility against dark wetsuit fabric or gear bags, making it easier to locate quickly in an emergency.

Built with the realities of underwater use in mind, the Tusa Blue Tang features a corrosion-resistant coating that helps the blade withstand repeated exposure to saltwater without pitting or dulling prematurely. The knife comes with a quick-release sheath system, allowing divers to mount it on a leg strap, BCD strap, or waistband, and to draw it swiftly with one hand even while wearing thick gloves. The locking mechanism on the sheath is designed to prevent accidental loss during a dive, while still allowing fast access when seconds matter, such as when freeing oneself from discarded fishing line or a snagged strap.

Compact and lightweight, the Tusa Blue Tang is well suited for recreational divers, underwater photographers, and instructors who need a reliable backup tool rather than a heavy-duty survival knife. Its smaller profile reduces drag and keeps the overall dive setup streamlined, which many divers appreciate when they are already managing cameras, lights, or other accessories. Overall, this knife reflects Tusa's broader reputation for thoughtful, diver-focused design, offering a practical safety tool that blends function, visibility, and comfort into a single, easy-to-carry package.