hat
2. Si R te swiv SS DS JJ, etc, mwayen ranfòse tip, ak R1 vle di sèlman yon de konba ranfòse ankò, R2 vle di de dantrènman avyon ranfòse ankò
eng
2.If R follows SS, DS, DD, etc, means reinforce type,and R1 means only one range reinforced, R2 means two ranges reinforced