Great Barrier Reef - HD 21'x41' Overlap Pool Liner - Above Ground Pool Liners, Quality Pool Products (21' x 41' oval) Vibrant High Definition - HD Exclusive Great Barrier Reef - HD - Vinyl Design - Swimming Pool Liners Overlap Pool Liner - Fits 48", 52", & 54" pool walls. UV protection from the sun's damaging rays. Kids love Sea Turtles