试试大小 meaning in English

try it for size

We need to try it on for size before buying it
（购买之前我们需要试试大小。）
You can try this jacket on for size
这件茄克您可以试穿上试试大小
Next , i tried the glasses on and found that they fit me perfectly , in terms of the frame size and lens prescription , and they allowed me to both read up close and see far into the distance
然后我把眼镜戴上试试大小，发现形状度数都非常适合我。这副眼镜不仅能近处看书，也能看远景，此刻我心里明白了：这是师父的恩典！