Each color represents a different charge range, so you know exactly when its time to recharge
Waterhouse PM, Smith NA, Wang M-B (1999) Virus resistance and gene silencing: killing the messenger
These previous studies [12,13,14,15,16,17] had several limitations such as the inclusion of relatively small number of cases, especially for rare type of congenital anomalies (i.e., being underpowered to detect small or moderate risk effect), the use of case-control design (i.e., being more prone to selection bias), or insufficient adjustment for potential confounders (i.e., being more prone to confounding bias)
Pretty amazing right
With reusable components, it is also more cost-effective and environmentally friendly than single-use devices
doi: 10.1111/j.1540-6237.2011.00820.x 231 WeissB.NguyenT.TrungL.NgoV.LauA