Amazon offers Prime members the Casio Men's Solar Easy-to-Read Watch in Black Dial, model no. MTP-S100E-1BVCF, or White Dial, model no. MTP-S100E-7BVC, for $19.99 with free shipping. (Non-members can spend $49 or more to qualify for free shipping; otherwise, shipping costs $4.48.) That's $35 off list and the lowest total price we could find. It features a 36.5mm stainless steel case, quartz movement, solar rechargeable battery, date display window, and water resistance to 165 feet.

Also available for Prime members is the Casio Women's Solar Easy-to-Read Watch in Black Dial, model no. LTP-S100E-1BVCF, or White Dial, model no. LTP-S100E-7BVCF, for $19.99 with free shipping. (As above, non-members can spend $49 or more to dodge the $4.48 shipping fee.) That's the lowest total price we could find by $11. It features the same specifications as the above model, but with a smaller 25mm case.