The K555 is a 32% K unknown composite motor from Contrail.
| Average Thrust: | 554.5270 N | 
| Certified By: | Tripoli Rocketry Association | 
| Class: | 32% K | 
| Delays: | 1000 seconds | 
| Diameter: | 54.0000 mm | 
| Length: | 1219.2000 mm | 
| Letter: | K | 
| Manufacturer: | Contrail | 
| Name: | K555 | 
| Peak Thrust: | 1,385.7900 N | 
| Propellant: | APCP | 
| Status: | In-Production | 
| Thrust Duration: | 3.0400 s | 
| Total Impulse: | 1685.7600 Ns | 
| Total Weight: | 2038.0000 g | 
| Type: | Unknown | 
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