$$-1 = under $50
$$-2 = above $50
$$$ = $100 or above
The mentioned DPI value is max. All mice have adjustable DPI.
Weight (±) Symbol
The (±) means that weights are adjustable.
All dimensions are in mm and in Length x Width x height format.
Laser vs Optical Gaming Mouse:
Optical mouse uses LEDS for movements tracking whereas Laser, as the name implies, uses Laser for tracking movements. Generally, Laser sensor is more responsive than optical but Optical is the most accurate.
DPI (Dot per inches) is a resolution focused factor that generally everyone throws around during discussion about gaming mice. It is correlated with sensitivity i.e. if you’re playing a game that requires quick movements than you would need a mouse that has higher sensitivity. So DPI basically means when you move your mouse, how fast or how further the cursor moves on the screen. It may also called CPI (Count Per Inches) some time. Following are the usual DPI numbers as per the game requirements (1)
High Sensitivity: roughly 1000 DPI needed
Medium Sensitivity: roughly 400 DPI needed
Low Sensitivity: roughly 200 DPI needed
Read More About Factors Effecting Gaming Mouse: Gaming Mouse Factors