Benchmade 290BK-1 Full Immunity

The Benchmade 290BK-1 Full Immunity is the Burnt Bronze version of Benchmade's small EDC folding knife with AXIS lock. The handle is anodised 6061-T6 aluminium in a warm bronze tone, and the 63.2 mm Wharncliffe blade is CPM-M4 with a Cerakote finish. At 65 g and 87.9 mm closed it takes up almost no room in a pocket, yet carries a blade built for precise work.

Full Immunity is Benchmade's take on a small folder with a high-performance steel and a full-strength lock. The Wharncliffe shape, with a straight edge and the tip in line with the edge, makes the knife well suited to cutting packaging, cord and precise cuts where you need to see exactly where the tip lands. The 290BK-1 has a Burnt Bronze handle; its sister model, the 290BK, is the same knife with a Crater Blue handle.

CPM-M4, Wharncliffe blade and AXIS lock

Five features that pack a lot of knife into a small format:

• CPM-M4 high-speed steel (62–64 HRC): A powder steel from the tooling world with high wear resistance and toughness. It holds an edge longer than most stainless EDC steels and tolerates high hardness without becoming brittle – but it is not stainless and needs more care.
• Cerakote finish: The ceramic coating protects the blade flats against rust and wear, which matters particularly on a non-stainless steel like M4. The edge itself is uncoated and must be kept dry and oiled.
• 63.2 mm Wharncliffe blade, 2.29 mm thick: The straight edge gives full contact with the cutting surface, and the tip is easy to control in precision work. The thin stock gives low cutting resistance.
• 6061-T6 aluminium handle: Anodised aluminium in Burnt Bronze gives a stiff handle at low weight. The handle is 12.7 mm thick and has a lanyard hole.
• AXIS lock and reversible Mini Deep Carry clip: The crossbar lock works the same from both sides, making the knife Ambidextrous. The black-oxide tip-up clip is reversible and lets the knife ride deep in the pocket.

Maintenance and safety

• Wipe the blade after use and always keep a thin film of knife oil on the edge – M4 is not stainless and can spot with rust if left wet.
• Give the AXIS lock and pivot a drop of oil now and then, and never use the knife as a pry bar or screwdriver.
• Keep your fingers clear of the edge when folding the blade, and guide it all the way closed with the lock pulled back.
• Check the regulations in your country before carrying the knife in public.