Screen retention assembly

A method of releasing a retention assembly securing an edge portion of a screen to a surround arrangement having a receiving channel formed by first and second opposed wall portions that receives the edge portion of the screen, the retention assembly including an engagement member having a substantially planar surface and an opposed wedging surface, wherein the wedging surface of the engagement member bears against a complementary wedging surface on the first wall portion of the receiving channel to capture and secure the edge portion between the second wall portion of the receiving channel and the substantially planar surface of the engagement member, the method including:

• further inserting the engagement member into the receiving channel to cause the engagement member to release and allow the edge portion to be removed from the receiving channel.

A lockable retention assembly for securing an edge portion of a screen to a surround arrangement, the surround arrangement including a receiving channel to receive the edge portion of the screen, the receiving channel formed by first and second opposed wall portions, the lockable retention assembly including:

• an engagement member for insertion into the receiving channel to secure the received edge portion of the screen in the receiving channel, the engagement member upon further insertion into the receiving channel operable to release and allow the edge portion to be removed from the receiving channel;
• a locking arrangement inserted through the first and second opposed wall portions and the engagement member to prevent either extraction or further insertion of the engagement member from the receiving channel.