Replace your inefficient and hot 10W halogen MR16 dichroic & reflector bulbs with these highly efficient and "cool" Imtra MR16 LED Replacement Bulbs.
These bulbs feature constant-current drive electronics for steady light output across the full 10-30V DC range. Warm-white high output LEDs combined with special linked optical lens results in uniform and satisfying illumination. The warm white color temperature matches typical halogen characteristics and is the preference for interior living spaces. Input voltage must be DC (direct current) from a battery source, LED converter, or DC power supply.

"MR" refers to multifaceted reflector, which produces a softer edge to the area of illumination than a smooth reflector.
MR number refers to bulb face diameter in eighths of an inch. MR16 = 16/8" = 2" Diameter.