Slide rail mechanism and slide rail assembly thereof

A slide rail mechanism, comprising:

• a first slide rail assembly and a second slide rail assembly, each of the first and second slide rail assemblies comprising a first rail and a second rail movable relative to each other, a locking member configured to lock the second rail relative to the first rail at a retracted position, and an operating member;
• and
• an unlocking handle movably mounted between the first slide rail assembly and the second slide rail assembly;
• wherein when the unlocking handle is moved from a first position to a second position, the unlocking handle is configured to drive the operating member to move linearly along a longitudinal direction of the second rail to further drive the locking member to move through contact between a first feature of the operating member and a second feature of the locking member, in order to unlock the second rail relative to the first rail at the retracted position;
• wherein the contact between the first feature and the second feature is a contact between two inclined portions, or a contact between an inclined portion and an arc portion.