With 72 Wh of energy, this quality battery is approved for air transport (see IATA regulations).

Number of flashes (at full power) per battery charge:
Siros 400 L: 440
Siros 800 L: 220

The battery must be recharged after a maximum of 5 months. If the batteries are not charged, they can fall into a deep discharge state and then usually cannot be recharged, i.e. they are defective and can no longer be repaired.

Li-ion battery 28.8 V / 2.5 Ah / 72 Wh
Dimensions (l × w × h): 8.5 × 11 × 5.5 cm (3.3 × 4.3 × 2.2")
Weight: 0.6 kg (1.3 lbs)
Battery charging time: approx. 75 minutes
Operating temperature range: −10° C to +60° C