fireworks air trap

Description,
This is a air trap that does medium damage but has splash damage. This trap makes little tiny explosions like fireworks.

unlocks at TH6
TH6: 2
TH7: 2
TH8: 3
TH9: 4
TH10: 4

Level 1
Damage per sec:15
Seconds of damage: 2
Damage range:4
Range:8
Rearm cost:10,000 gold

Level 2
Damage per sec:15+5
Seconds of damage:2+0.5
Damage range:4
Range:8
Upgrade cost:250,000 gold
Rearm cost:15,000 gold

Level 3
Damage per sec:20+5
Seconds of damage:2.5+0.5
Damage range:4+0.5
Range:8
Upgrade cost:500,000 gold
Rearm cost:20,000 gold

Level 4
Damage per sec:25+5
Seconds of damage:3+1
Damage range:4.5+0.5
Range:8
Upgrade cost:750,000 gold
Rearm cost:30,000 gold

How is this different from a air bomb?