For  Olympus/Panasonic/ Leica.  This hghly recommended speedlight - flash gun - was never used after purchase and is complete in its pouch with box and instruction booklet.  It is neat and lightweight .  Here are the manufacturer's specs:  

Meike MK-300 Flash Light TTL Speedlite
1) High Guide Number: 32
2) Recycle time 6 second (with 2pc AA alkaline cell)
3) Flash mode: TTL, M, RPT
4) 22 fine adjustable of flash output control
5) Compatible with TTL flash automatically
6) Power saving mode
7) Accurate brightness control
8) LCD display

Circuit design: Insulated Gate Bipolar Transistro (IGBT)
Guide Number: 32 meters (ISO100, 105mm)
Flash mode: TTL, M, RPT
Power supply: 2x AA size batteries (Alkaline or Ni-MH are useable)
Lighting times: 100-1500 times (AA alkaline cell used)
Recycle time: approx. 6s
Color temperature: 5600K
Flash time: 1/200s-1/20000s
Flash control: 1/128~1/1
External interface: hotshoe, Mini USB
Additional features: FEC
Size: 80 x 66 x 62mm

Net weight: 145ging