FillPro Soft Type Backer Rod is a pliable bi-cellular PE foam material used for filling irregular joints. It is chemically inert and will resist oil, gasoline and most other solvents. The material will not stain, or adhere to sealant materials and is non-exuding. It’s available in spools in 3/8” to 1 1/8” diameters or 6’ lengths for sizes over 1 ½” up to 4”diameter. Its unique construction is highly compressible, but has a closed cell outer skin to resist moisture. Particularly suited for specialty applications where standard backer rods are not appropriate, FillPro Soft Type is ideal in irregular joint applications particularly where self-leveling, flowable sealants are employed. Also recommended with sealants where bubbling concerns are critical. An excellent all-purpose backer rod, it may be used in place of most standard backer rod applications.