The present invention discloses a catheter instrument 1000 comprising a needle tip shielding device 100. The needle tip shielding device 100 is comprising a body with a rear side 106, a front side 107, an outer surface 108 connecting the rear side 106 and the front side 107, a hole 102 extending from the rear side 106 to the front side 107, a resilient arm 103 extending at an attachment point 105 from the front side 107 of the body, and a longitudinal arm 112. The resilient arm 103 has a resting state, from which it may be forced to yield free passage through the hole 102 in an axial direction of the body. The resilient arm 103 is adapted for protecting a needle tip 304 of a hollow needle 303 extending through the hole 102 in a direction from the rear side 106 to the front side 07, when the resilient arm 103 is in the resting state. The resilient arm 103 has one external point of contact, the point of contact being a contact with the hollow needle 303 when the hollow needle 303 is in a forward position. The longitudinal arm 112 has one external contact point, the contact point being a contact with the hollow needle 303 when the hollow needle 303 is in a forward position. Any straight imaginary line extending longitudinally through the hole 102 in the axial direction of the body coincides with the resilient arm 103, when the resilient arm 103 is in the resting state.