Part Numbers: FYK4G, 61KCY, 24V27, H4X64, K7F3P, WYMD5. Compatible Models: R520, R530, R540, R540-XD, R720, R720-XD, R730, R730-XD, R740, R740-XD, R7415, R7425, R820, R830. Rails: Rail Kit (Inner & Outer).
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