Recently, the improvement on space and time resolution of in-situ instruments makes the small-scale flux ropes the hot point in the study of solar wind. Previous works analyzed the in-situ measurements from WIND between 1995 and 2005, and they reported two different lists of small-scale flux ropes with only 4 cases in common. The two lists were selected by human vision and by computer program, respectively. A recent work surveyed the list from human vision, finding magnetic reconnections in the boundary layers of 42% small-scale flux ropes. In order to reveal the magnetic reconnection properties at small-scale flux ropes' boundaries from both lists, we analyzed the computer selected list, finding magnetic reconnection happened at the boundaries in 41% of the flux ropes. Furthermore, other properties also indicate the two flux rope lists have almost the same trend statistically. These properties include magnetic reconnection shear angle, decrease of magnetic field magnitude and observational time scale of reconnection exhaust. Since more samples give more confident results, we combine the magnetic reconnection events in both lists, totally 71 magnetic reconnection exhausts. Our result shows 70% with a magnetic field strength depression larger than 20%, about 66% of the magnetic reconnection events are associated with a magnetic field shear angle larger than 90°. This indicates that the magnetic reconnection at the boundaries of the small-scale flux ropes are more likely to be anti-parallel than the reconnection events in the solar wind. Meantime, this result supports the previous work result based on the human vision selecting list. Our discussion first demonstrated the leading edge magnetic reconnections and the trailing ones have similar signatures, implying boundaries of small-scale flux ropes are different from the magnetic clouds. Therefore, the small-scale flux ropes do not expand as their larger scale counterpart- the magnetic clouds.
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