HarderWill 3 in 1 Yoga Foam Wedge Blocks (Pair), Calf Raise Block, Yoga Strap Set, Calf Stretcher, Yoga Wrist Support, Balance, Pushup, Fitness, Pilates, Heel Stretcher, Squat Wedge with Gym Bag

These are very light, sturdy and good quality.

As described, perfect for what i need and sturdy enough.

Works great, light weight but sturdy.

I use these to raise my heels for certain squat variations. It's kind of frivolous since you can just put some plates or plywood under your heels, but the grip on these is actually pretty nice to have.

affordable and i like the flat back - using this as a mini-ramp for my dog who can't quite make the step jump. Great option and sturdy, but lowered my rating because of quality control. They aren't the same height, off by a few mms, so makes it hard to line them up side by side for my use-case.