Rocket motors B6-4 (Pk3)

Estes B6-4 engines. This pack contains 3 engines with 4 igniters and 4 plugs.

The engine name is made up of 3 identifiers.
B = The engines impulse, each letter doubles. The A motors have 2.5N/s of impulse. (B engines would have 5N/s and C engines 10N/s).
6 = The average thrust in newtons during the burn.
4 = The delay before the parachute ejection charge goes off. 0 means a booster stage, and P means a plugged motor with no ejection.