These large diameter slick rods come in 4 different sizes. The 1/2" are perfect for liners and small flue tiles up to 7" round. Use for almost all wood stoves and inserts. For use as first rods in 6" wood stove or insert flues, follow w/ 5/8" rods. The 5/8" size is new, It flexes like the old 7/8" black poly rod, But it bends further without danger of kinking. This size is ideal for masonry chimneys. Offsets are no problem, It is stiff enough to resist bending and flopping all over in everything but the largest flues, say over 12x16.Some folks will even use this size for deglazing with chains and cable loops although our larger 3/4" rod may be a better choice.However for flues with creosote and offsets this may be the only way to get beyond the bend.The 3/4" size solid Slick rod is new, we've had 3/4" rods before but those are hollow. Fully capable for use when creosote deglazing and tile breaking w/ButtonLok Tools. They are easier to handle than steel rods with less breakage. They deliver the torque to the tool with minimal "windup" which can occur when you have lots of rods together.