A needle cannula, an injection needle assembly for an injection device and an injection device comprising such assembly

An elongated tubular needle cannula for an injection device, the needle cannula extending along a central axis and comprising:

• a skin piercing distal end,
• a proximal end arranged axially opposite the skin piercing distal end the proximal end being configured for penetrating a seal structure of a medicament container,
• a sidewall extending between the skin piercing distal end and the proximal end, and
• a lumen extending through the needle cannula along said central axis, said lumen has a first opening arranged axially at the skin piercing distal end and a second opening arranged axially at the proximal end wherein the proximal end being defined by an angled surface pointing proximally, the angled surface intersecting with the sidewall at a proximal-most point defining a leading portion and intersecting with the sidewall at an oppositely arranged trailing portion defining a heel portion,
• wherein the angled surface pointing proximally comprises a surface portion at the heel portion forming an angle (α1) between 50 to 75 degrees with respect to the central axis, and further comprises a surface portion at the leading portion forming an angle (α2) between 60 to 85 degrees with respect to the central axis.