premium grade

基本解释

Our Tall Venice Boots are manufactured from premium grade sheepskin pelts.
我们的高的威尼斯靴子被由高级的等级毛皮制造成。
dict.cn
The paper inhibitor was heavy premium grade art paper of 0.0095 inch (0.24mm) thickness.
文件抑制剂是沉重的保费级铜版纸的0.0095英寸（ 0.24毫米）厚度。
Additional charges for oil should only be made if more than four liters are used, or if the customer requests a premium grade oil (such as a synthetic oil).
只是在使用四升以上的油或顾客要求优质油（如合成油）时才应该收取额外的邮费。

According to the EPA, a motorist who drives the Volt exclusively on electric power will pay an estimated 4 cents per mile in energy costs, while one who never recharges the battery and runs the car exclusively on gasoline (with premium grade required) will pay 9 cents per mile.
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My analysis indicates, rather, that the risk premium on investment grade corporates is generous, making that group attractive by comparison.
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There's evidence that the risk premium is peaking for investment grade corporate debt.
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