【Safe for Pool Liner】The smooth and round finishing edges as well as the premium nylon bristles of the pool brush are gentle on pool liners and painted pool floors, so there are no scrapes or snags to pool surfaces，even to vinyl pool liner.
(Publisher: Sepetrel. The curved edge design allow you to get the hard corners without the worry of cutting the pool liner（safe for vinyl liner). Works with most 1-1/4" standard pool pole (pole not included).
【Heavy Duty】VNW rafter square made of precise and durable CNC-machined aluminum alloy. Good oxidation resistance, not easy to break, each triangle ruler is thickened, corrosion-resistant and high hardness.