The B4 Q-Jet (B4) is a 94% B single-use motor from Quest.
AeroTech's Black Max propellant produces a dense black exhaust.
The casing of this motor is 70mm in length (the same as a standard 18mm motor).
| Average Thrust: | 4.4182 N | 
| Certified By: | National Association of Rocketry | 
| Class: | 94% B | 
| Delays: | 4,6 seconds | 
| Designation: | B4 Q-Jet | 
| Diameter: | 18.0000 mm | 
| Formula: | Black Max | 
| Length: | 80.0000 mm | 
| Letter: | B | 
| Manufacturer: | Quest | 
| Name: | B4 | 
| Peak Thrust: | 7.2000 N | 
| Status: | Out-Of-Production | 
| Thrust Duration: | 1.1000 s | 
| Total Impulse: | 4.8600 Ns | 
| Total Weight: | 19.8000 g | 
| Type: | Single-Use | 
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