门横框(trim)上加钉4,5 颗 finishing nails, 绝对不会掉下来 (尽管如此, 小命要紧, 做的时候下面放个 bean bag, just in case)。
这个像我买的:
https://www.amazon.com/Sagler-Pull-Doorway-Heavy-Trainer/dp/B01N2HAQEE/ref=asc_df_B01N2HAQEE/?tag=hyprod-20&linkCode=df0&hvadid=216527880203&hvpos=&hvnetw=g&hvrand=16362200227753250460&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=2840&hvtargid=pla-379205704004&psc=1