A tongue mechanism for use in an occupant restraint system also having a buckle mechanism and a webbing. The tongue mechanism includes a tongue member configured to selectively engage the buckle mechanism, a body formed over a portion of the tongue member, a slider, and a biasing member configured to laterally bias the slider. The body includes a body contact surface. The slider includes a slider contact surface and is configured to travel along a track between a first free position and a second locking position. When the slider is positioned in the first free position the tongue mechanism is free to slide along the length of the webbing, and when the slider is positioned in the second locking position a portion of the webbing is clamped between the slider contact surface and the body contact surface thereby preventing the tongue mechanism from sliding along the length of the webbing.