Pack of 2 High Quality Brushes Cleans grime & scum lines Gentle brush won't scratch surfaces Great for cleaning jets & filter housings Made in USA - Very Durable We call it the Harmless Spa Brush because it's 100% safe on all spa surfaces. But don't let the name fool you, this brush quickly destroys tub rings, scum, and grime. Shines and cleans spas and bathtubs with no risk of scratching. There's nothing else like it! What's the secret? Instead of sharp bristles which can scratch your spa's acrylic surface, the Harmless Spa Brush uses over a thousand tiny closed-cell foam pads to gently scrub the surface while reaching all of your hot tub's nooks and crannies. Also excellent for use on showers, sinks, tiles, autos, boats and any surface that you want to clean without damage.