An adjustment device for an awning is provided comprising an engagement member and a resilient adjustment member having an outer diameter. The outer diameter of the adjustment member is adapted to be selectively adjustable. A retainer element is provided to maintain a desired outer diameter. In one example, the resilient adjustment member can be adapted to engage the engagement member. In addition or alternatively, the engagement member can have a plurality of angular splines that are keyed into corresponding internal grooves of the adjustment member. In addition or alternatively, the resilient adjustment member can be adapted to splinably engage the engagement member. In addition or alternatively, the resilient adjustment member can have a plurality of support members and a plurality of flexible connectors, wherein each support member is connected to an adjacent support member by a flexible connector to form an enclosed cross-section.