The goal of this puzzled is to fit all 5 wave-shaped pieces into the tray provided.  As with other of Yuu's puzzles, this quality plexi packing looks better than the picture can depict.  Each piece is made from acrylic and fits into the sturdy white plastic base.  The solution may be more difficult than you would expect.
Top 10 Vote Getter at the IPP 2019 Competition
The tray measures: 13.6 cm x 10.4 cm x 0.6 cm / 5.4 in x 4.1 in x 0.25 in

• See at Puzzle Master