不懂，但是leol的presto蛮火的，我买的CR03蓝色53码,因为买的工具和一点小配件没到货所以还没开始装

雷诺520是雷诺生产的管材型号，铬钼钢4130是原材料标号，他俩是同一个东西。
“520 is the proprietary designation for a range of butted frame tubes made by Reynolds using a chromium molybdenum steel alloy similar to the AISI 4130 standard.
Other manufacturers also make butted frame tubes of AISI 4130 chromium molybdenum alloy.
The raw material used for Reynolds 520 is essentially 4130, so the difference between 520 and 4130 is that 520 refers to the finished tube sets from Reynolds, while 4130 is simply a steel alloy that other manufacturers use to make their own tube sets competing with Reynolds 520.
Not just similar, but actually 4130.”