The RD-210 FPV Racing frame is one tough frame! The 4mm arms are starting to become a standard for many miniquads. This one is no exception. The 4mm arms paired with the lower plate and a bottom plate underneath the arms makes this frame very thick! However, the extra thickness does not add too much weight in comparison to other quads.
The only down sides to this frame are the extra carbon fiber parts I don't know what to do with and the screws could all stand to be 1mm - 2mm longer. Especially those that are going through the arms into the metal spacers and the nylon spacers for the flight board/PDB.
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You can get your own here:
RD-210 Frame:
Other frames in the video:
Martian 255 frame:
GE220 Frame:
Drumming is from the "100 Year Old Drummer":