Ekornes Stressless swivel recliner chair BASE PLASTIC SWIVEL RING 653mm 65cm

This is not a riser. This is the gliding swivel ring that allows the chair to spin in the floor. Look carefully at the measurements as the size depends on the type of chair and age. So there are numerous variations not just the S/M/L. The maximum diameter of this is 653mm, (the other side is mm narrower). See pics for more details.

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