Hardware Kit, 3D Printable Split Gearbox V2

The PolarStar Hardware Kit includes all required fasteners and components to assemble the free 3D printable V2 gearbox lower — no hardware store runs, no guessing on specs. Print the lower, grab this kit, and build.

What's Included:

Qty	Part	Purpose
4x	Screw, BHSC, M3 x 15mm SS	Clamshell assembly
1x	Screw, BHSC, M2 x 4mm SS	Switchboard mount
8x	Heat Set Insert, M3	Clamshell + grip screw inserts
1x	Heat Set Insert, M2	Switchboard insert
1x	Square Nut, M5	Buffer tube screw
1x	#23 HSS Drill Bit	Grip screw pilot holes
1x	Compression Spring	Pusher piece — keeps engine seated forward
2x	Bullet Valve Lead, 5"	HPA line routing

Compatible With: Free PolarStar V2 Gearbox Lower files — download at polarstarairsoft.com/pages/creator-corner or grab the Bambu-ready 3MF on MakerWorld.

Notes: Heat set inserts require a soldering iron set to 200–230°C. Vertical clamshell holes are pre-sized after printing — no drilling needed for those locations. Grip screw pilot holes require the included #23 drill bit before insert installation.

The free 3D printable gearbox files are required to use this kit. HPA Engine, Direct Attachment Front Cylinder, and Hop Up Thing are sold separately.

Complete your build: For a full DA gearbox build you'll also need a selector plate and trigger/safety assembly. Both are available separately:

M4/M16 Series Selector Plate
VFC M4/M16 Fusion Engine Small Parts Kit

M4/M16 Series Selector Plate (GEN3 Only)

VFC M4/M16 series Fusion Engine Small Parts Kit

Hardware Kit, 3D Printable Split Gearbox, V2