Amazon offers its Prime members the BlenderBottle SportMixer Protein Shaker 28-oz. Cup in Clear/Orange for $6.99 with free shipping. (Non-members can spend $35 to qualify for free shipping; otherwise, shipping adds $5.55.) That's $5 under our March mention and the lowest total price we could find by $1. It includes a sport loop, ounce/milliliter markings, and wire wisk.

Of note, Amazon also offers Prime members the BlenderBottle SportMixer Protein Shaker 20-oz. Cup in Clear/Orange for $5.99 with free shipping. (Non-members can spend $35 to qualify for free shipping; otherwise, shipping adds $5.46.) That's the lowest total price we could find by $2.