Description

Remade and upgraded CNC gearbox from Retro ARMS with code name “7075 series”.
Gearbox version II is completly milled at CNC machining center. Compared to other aluminium gearboxes, our is made out of solib block of aluminium AW EN7075 T651. Source block weighs 1550g and only 143g of material are left. It is not casted like Chinese ones! Our gearbox is tested wit M160 spring without any signs off wear or breaking long term. Gearbox’s surface is decoratively anodized.
It’s available with slots for 8mm. Bearings are not included. You can choose them from our offer here.
Gearbox is equipped with quick spring change system – QSC. Our CNC spring guide is included.
New features and upgrades:

reduction of wall thickness – it can be used in most of M4 guns without problems
reduction of plugs for cylinder head (1) – cylinder heads from all makers can be used
сделаны for bigger air flow (2)
control window for AOE (3)
control window for piston position check (4)
removing of radiuses around place for trigger contacts – ASCU contacts can now be used without problems (5)
widening of hole for central pin – gearbox can be installed into non-standard bodies e.g. PJ (6)
windows for lubing gears (7)
opening for releasing anti-reversal latch (8)
remade holes for using screws with cylindrical heads plus new strength screws (9)
new wrought threads – compared to old cut ones
go-through window for cables under motor post (10)
milled shoulder above motor cables under motor post (11)
more edges bevelled by machine
adjusted front part of the gearbox allowing use of more Hop Up Chamber types (12)
new laser labels with unique serial number
new strength screws

All standard parts for gearbox version II can be used of course. Both halves fit together with absolute precision including bearing holes, which are 100procent co-axial.
Further small features:

accurate hole for Anti-Reversal Latch – it doesn’t fall out
accurate hole for trigger – it doesn’t jump out even with strong spring
micro grooves on pins, which hold trigger..