Replicas have spring, electric or gas propultion. Spring models need to
reload after each shot (pull back the lock) to enter the ball into the chamber.
At the same time it pulls spring back, to be able to give a shot. Electric
replicas depends on the battery, whereby the engine drives the whole gearbox,
and a gas models, push the BB by gas, which loads in magazine (in these replicas
ther is not spring).

It is the spped of bb, while its leaving the
innerbarrel of replica. This speed is measured in FPS (Feet Per Second).

1 FPS = 0,3 ^m/_s

1 J = 99 ^m/_s

1 J = 326,7 FPS

The length of the replca is measured between the
two most distant points of each other. Different models have several of these
values, because of its design allows to increase or decrease it length (eg.
folding stock or extended flash hider).

This is a value that includes the weight of the
replica, magazine and other accessories that are include in set without a
battery, charger, cleaning rod, etc., etc.

Hop-Uup system is used for overclocking bb during
the shot (putting it in rotation), through which, it extends its flight path.
Acting laws of physics make that bb lift up, while the gravitational force take
it down. Appropriate adjustment of Hop-Up, will compensate for these two
factors, which result in long and straight flight for longer distance and be
greater focus shot (to improve accuracy).

Blow back is a simulation system of the cocking lever - it imitates the work
of it as the equivalent sharp. This system raises the realism and adds a lot
more experience during shooting.