グリップマスター™ 極限握力トレーナー ─ 7分で前腕が悲鳴を上げる

GripMaster™极限握力训练器声称可在7分钟内显著增强握力和前臂肌肉，适用于日本人，并提供3周内前臂血管浮起的退款保证。

• The description claims that GripMaster™ can significantly enhance grip strength and forearm muscles in just 7 minutes.
• The description claims a refund guarantee of full amount if the veins do not pop out on the forearms within 3 weeks.
• The description claims that users can feel grip strength improvement within one week, visible results within three weeks, and become a different person's arm within eight weeks.