Recommendation for a grip strengthener

Over at the relaunched, I asked readers to recommend a good grip strengthener.

Grip strengtheners. Some are lever-based and work all the fingers at once. Others are like a trumpet, with individual pegs for your fingers. Others are squishy balls/donuts. I'm mainly interested in improving forearm strength while I watch TV, listen to podcasts, etc. What do you recommend?

Answer this question here.

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