This is the B6-6 Standard Model Rocket Engines/Motors from Estes.
Suitable for Ages 10 & Older with Adult Supervision for Those Under 12.
Three B6-6 Engines
Four Igniter Plugs
Upper stage engine
Engine can also be used as a single stage engine in lightweight
Engines tested and certified by the NAR
Easy to use and comes with clear instructions
Length: 2.75" (7cm)
Diameter: .69" (18mm)
Adult Supervision for Children Under 12