This double-ended applicator brush has soft 0.003" brass wire at one end and a sponge at the other. The handle is made of corrosion resistant, zinc-plated steel tubing. This brush is manufactured using strong mechanical clamping for maximum fiber retention, and is adhesive-free to prevent contamination to work pieces caused by leaching. The fine brass wire is densely packed and has a flat end trim of 1/2" length with a width of 7/16". The sponge end flares out to approximately 1-3/8" x 3/8" when wet. The handle dimensions are 4-1/2" length x 3/8" diameter. This versatile, high-quality wire/sponge combination brush is great for cleaning soldering iron tips. Use the wetted sponge to wipe excess solder from a hot iron tip and the brass wire end to polish it. The brush is also ideal for fine detail cleaning when you need to wet a surface prior to brushing.