ESA, SAEC (Specna Arms QSC)

ESA is a Quick Spring Change (QSC) system used in Specna Arms airsoft guns.

Specna Arms offers several spring change systems:

ESA (EDGE, CORE, Flex series) - No need to remove the gearbox from the gun, but you have to unscrew the stock tube, screw, and stock tube washer)

ESA2 (EDGE 2.0) - No need to remove the gearbox from the gun, just loosen the stock tube with a key and unscrew the end cap to access the spring)

SAEC (some models of the ONE series and others) - Similar to ESA2 (No need to remove the gearbox from the gun, just loosen the stock tube with a key and unscrew the end cap to access the spring)

Enter & Convert™ (some models of the ONE series and others) - You have to remove the gearbox from the gun!

SAEC/ESA2