Abstract: A seal for covering a track in a floor is disclosed which is flexible in the upward direction to permit an arm or the like moving on the track to pass through the seal and is considerably less flexible in the downward direction into the channel and capable of supporting a person or equipment traversing the channel. The difference in flexibility in the two directions is obtained by providing a relatively thin material in the area of the hinge section and a relatively thicker material in the cover portion extending over the channel. The relatively thicker material section may be formed by affixing a narrow strip of flexible material to a wider strip of the material. The narrow strip may be affixed to the wider strip by welding or fusing.