The SOPMOD Block 3 or more commonly known URG-I (Upper Receiver Group Improved) is a rifle model currently used by several United States special forces units.
The URG-I is designed to be an upgrade over the venerable MK18 and SOPMOD Block 2 versions of the M4 and boasts improvements over its predecessors.
Upgrades like a slimline M-LOK handguard, an improved bolt carrier group, and an enlarged cocking handle are some of the easy-to-spot differences between the URG-I and other M4s.

The VFC Avalon M4 URG-I is part of the VFC Avalon Premium line and has been further improved.

Internally, the VFC Avalon features the VFC ECS gearbox with the GATE ASTER system installed. This immediately makes it one of the best replicas right out of the box. The GATE ASTER features programmable electronics, such as a trigger proximity sensor that allows you to fine-tune 250 sensitivity settings, a binary trigger function as a default setting, an optical cam sensor that supports all types of gears, and allows you to program the firing mode of the guns from semi/full auto to semi/controlled burst, for example.
In addition to this impressive list, the Avalon comes standard with Maple Leaf internals such as a rubber hop-up and a precision-machined inner barrel that allows for tighter groupings and longer throw. Finally, the Avalon is Deans (T-Plug) ready.

Manufacturer: Vega Force Company
Model: Avalon M4 URG-I
Material: Full metal
Weight: 3000 g
Length: 700mm-780mm
Inner barrel: Precision, 275 mm
Magazine: 120-round mid-cap
Shell: All metal with screen printed logos
Rails: Metal top for accessories and M-Lok compatible handguard
Mode of action: electric
Firing mode: single/burst (programmable)
Battery compartment: in PDW stock - mini type DEANS connector recommended
Battery and charger excluded
Floating aluminum front
Advanced version with electronic trigger and Gate Aster control unit

Technical Features
Gear box: Fully metal reinforced
Hop up: Maple Leaf Competitive Grade adjustable
Hop up rubber: Maple Leaf 60°
Engine: Long axle high speed
Gears: Custom steel
Bushings: 8mm steel high speed bearings
Piston: Reinforced polymer
Piston head: Reinforced polymer
Cylinder: Match Grade Aluminum
Cylinder head: Reinforced polymer
Spring: 1 joule
Ball Pusher: Reinforced ABS
Inner barrel: Precision aluminum maple leaf

Equipment:

VFC AVALON M4 URG-I
1x Mid-cap Charger