查到這個，是講after tax 401k， 可以有 43500， 所以， 總和7.3萬， 差不離了

They can put up to $43,500 of post-tax dollars in 2023 into their 401(k) plan and then roll it into a mega backdoor Roth, which is either a Roth IRA or Roth 401(k).