The present invention provides a seal comprising an elastomeric composite, said composite comprising an elastomeric polymer and a negative thermal expansion (NTE) filler, the NTE filler has a coefficient of thermal expansion (CTE) lower than ?6?10-6 K-1 within a temperature range of 220-293 K and is present in an amount of 0.01-50 volume % based on the total volume of the elastomeric composite at 20? C.