Interlocking Foam Mats. Each mat size: 600 mm x 600 m/ 24 "x 24 " /2ft x 2ft. Non-Slip, Anti Slip Pattern Finish. You can even take these with you - take them apart, put them down to 24" x 24" (600 x 600mm) (easy to fit into the car, or under your arm then), and take them camping, on picnics, etc.
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