Amazon.com.au:Customer reviews: Memory Foam Back Cushion by CompuClever-Lumbar Support Pillow with Dual Adjustable Straps-Lower Back Support Cushion for Home Office Chair Car Seat Ergonomic Design with Removable Cover
Arrived promptly well packaged. Gave me the support I need on my office chair. The elastic is on the long side so it dangled a bit on the top half - not tightly held on chair - but does not matter, as once you sit back it sits well. It can easily be shortened I just haven’t gotten around to pinning it.
This cushion does exactly what I wanted it to! Hooks around my chair easily and certainly promotes better posture. My husband used it when his back was hurting & found it effective as well. I would recommend it!