High-Class
High Grade, High Level
noun, な adjective, の adjective
A tall grade item is really just a high grade or high-class item.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.
高級バージョンのワニカニがものすごく売れたおかげで、トーフグの名前に箔が付きました。
The high level version of WaniKani sold really well and made the Tofugu name increase in value.
高級茶を一ぱいごち走させて下さい。
Let me buy you some high class tea.
この高級レストランはビップ専用となっているので、入店するには招待状か紹介状が必要になります。
This high end restaurant is for VIPs only. In order to enter, you need an invitation or a letter of referral.