deflecto CM14142BLK SuperMat Frequent Use Chair Mat, Medium Pile Carpet, Beveled, 36 x 48, Black Protective vinyl chairmat safeguards and protects carpets from wear and tear Medium weight chairmat for frequent use on carpets up to 1/2" thick, Medium Pile; choose a higher pile chairmat if usage is over 6 hours Easy-glide rolling surface provides effortless chair movement