Large Ejection Canisters are suitable for larger models than our standard SEC-5a canisters. As a rule of thumb they are intended for models from 4 inch to 5.5 inch diameters, but the volume an ejection charge has to pressurize will vary greatly with the rocket design. We strongly recommend ground testing the complete recovery system of your rocket.

LWEC-5A Large Ejection Canisters are single-use devices and come in packs of 5. They are packaged in a tamper-proof reusable zilpock bag. The resistance of the filament is measured continuously while Ejection Canisters are being made, for quality assurance. The resistance is written on the side of the Canister. Use a multimeter to measure the resistance of the Canister before use; if it varies more than 10 ohms return it to us for a free replacement.

Detailed information here