For the stability design of members and sets of members with a uniform cross-section, you can use the equivalent member method according to EN 1993-1-1, 6.3.1 to 6.3.3. However, as soon as a tapered cross-section is available, this method can no longer be used or only to a limited extent. The RF-/STEEL EC3 add-on module can automatically recognize such cases and switch to the general method.