A USB to hub with PD, HDMI, VGA, and audio typically offers a combination of ports for connecting multiple devices and peripherals to a single USB-C port. Key specifications include data transfer speeds for USB, supported resolutions for HDMI and VGA, power delivery (PD) wattage, and audio output capabilities. 
Key Specifications:
USB Ports:
USB 3.0/3.1/3.2: Data transfer speeds can range from 5 Gbps to 10 Gbps or even 20 Gbps for newer versions. 
USB 2.0: Offers slower data transfer speeds, typically 480 Mbps. 
HDMI Port:
Resolution: Supports various resolutions, including 4K at 30Hz, and potentially higher resolutions like 4K at 60Hz with HDMI 2.0 or 2.1. 
VGA Port:
Resolution: Typically supports resolutions up to 1920x1080 (1080p) at 60Hz. 
Power Delivery (PD):
Wattage: Can range from 60W to 100W or more for fast charging of laptops and other devices. 
Audio:
3.5mm Audio Jack: Allows for connecting headphones or speakers. 
Other Features:
SD/TF Card Readers: May include slots for accessing SD and/or TF (microSD) cards. 
Ethernet Port: May offer a 100Mbps or Gigabit (1000Mbps) Ethernet port for wired network connectivity. 
Compatibility: Compatible with devices that have a USB-C port, including MacBooks, Chromebooks, and other laptops. 
DisplayPort Alt Mode: To use HDMI and/or VGA output, the host USB-C port on your device must support DisplayPort Alternate Mode (DP Alt Mode). 
Example Specifications (from search results):
11-in-1 USB C Adapter: Offers HDMI (4K@30Hz), VGA (1080P@60Hz), USB 3.0 (5Gbps), PD (100W), SD/TF card readers, and a 3.5mm audio jack. 
USB C Hub with HDMI, DisplayPort, VGA: Features HDMI, DisplayPort, VGA, USB 2.0, fast Ethernet, and 60W charging. 
USB C Docking Station (8-in-1): Includes 2 HDMI (4K@30Hz), 1 VGA (1080P), 3 USB-A 3.0, and a charging port.