These are just brilliant! If you fly clusters or staged rockets, this is the best thing since sliced bread.
50 to a pack
For staging, just snug one of these in the nozzle of the second stage (sustainer) motor for an instant ignition of the motor. Very little if any tip over if any. Just staging one motor into another (without an igniter stick) invariably tips the rocket off vertical during the ignition delay. Fly higher and faster!
For super reliable cluster ignition, snug one of these into each nozzle. They fit perfectly in Klima nozzles (for Estes motors you may need a bit of masking tape to make that snug fit). Then use Klima TapeMatch to provide the virtually instantaneous combustion link. Goodbye asymmetric thrust!
The Model Rocket Shop swore by (and occasionally AT) QuickMatch for years. We no longer offer that far more fiddly product with the availability of TapeMatch.