It is Bluetooth 2.0 Module+PIC18F25K80 Chip Hardware V1.5,please check Real PCB Board(2PCB Board on Main Unit): 

2PCB Board Version MAC Address:
AA:BB:CC:11:22:33

Model 2 New 1PCB Board Display:
It is Bluetooth 2.0 Module+PIC18F25K80 Chip Hardware V1.5,please check Real PCB Board(1PCB Board on Main Unit):

1PCB Board MAC Address will be Random

Hardware V1.5, it is more stable and supports more cars than ELM V2.1. Hardware V1.5 is More Powerful than V2.1. 
Hardware V1.5 Supports SAE J1850 PWM and SAE J1850 VPW.
V1.5

item description
Super MINI 100% V1.5 Hardware ELM327 Bluetooth Scanner
Bluetooth 2.0+Best PIC18F25K80 Chip,best quality to send!
PIC18F25K80
ELM327 V1.5 Highlights:
ELM327 MINI OBD SCAN is the newly developed wireless scan tool. It supports most standard OBD-II protocols
Hardware V1.5  ,Soft ware V2.1
Bluetooth Password  :0000 / 1234 / 6789
Woks on Android Torque   (support Android smart phone System with Android 4.0-Android 4.4 version)  /PC( win XP/WIN 7 32bits and close anti-virus programm)
It can not supports iOS,if u need works iOS,please buy ELM327 WIFI.
It CAN’T support Trucks.

This ELM327 Hardware V1.5. supports most of OBD-II protocols cars,but it can not do all models 
With Chip PIC18F25K80,it supports Diesel&Gasoline Multi-Cars.
Supprots All OBD2 Protocols:

SAE J1850 PWM (41.6 kbaud) 

SAE J1850 VPW (10.4 kbaud) 
ISO9141-2(5 baud init,10.4Kbaud)
ISO14230-4 KWP(5 baud init,10.4 Kbaud)
ISO14230-4 KWP(fast init,10.4 Kbaud)
ISO15765-4 CAN(11bit ID,500 Kbaud)
ISO15765-4 CAN(29bit ID,500 Kbaud)
ISO15765-4 CAN(11bit ID,250 Kbaud)
ISO15765-4 CAN(29bit ID,250 Kbaud)

This link is ELM327 Hardware V1.5,it is more stable and supports more cars than ELM V2.1. Hardware V1.5 is More Powerful than V2.1. 
Hardware V1.5 Supports SAE J1850 PWM and SAE J1850 VPW.
Supports CAN Protocols also other protocols.
Default Settings(user adjustable)
1.Works with OBD-II compliant vehicles
2.Wireless (Bluetooth) 5~10 meter
3.Soft ware included for Pa, PDA,Mobile
4.Soft ware included for Windows PC ,Can also be used with a PC with a Bluetooth Card.

5.Soft ware included for Windows Smartphone Android torque 

Functions: 
Read diagnostic trouble codes, both generic and manufacturer-specific, and display their meaning (over 3000 generic code definitions in the database).
Clear trouble codes and turn off the MIL (“Check Engine” light)
Set the maximum number of responses to obtain
Remove spaces from ECU responses (to speed data transmission)
Store a unique identifier in EEPROM
Set the CAN mask and filter with one command
Easily switch between variable and fixed CAN message lengths
Send CAN remote frames (RTRs)
Display current sensor data, including:
Engine RPM
Calculated Load Value
Coolant Temperature
Fuel System Status
Vehicle Speed
Short Term Fuel Trim
Long Term Fuel Trim
Intake Manifold Pressure
Timing Advance
Intake Air Temperature
Air Flow Rate
Absolute Throttle Position
Oxygen sensor voltages/associated short term fuel trims
Fuel System status
Fuel Pressure
Many others.
Multi-Language 12kinds:
Czech,Danish,German,English,Spanish,French,Croatian,Hungarian,Italian,Polish,Serbian,Turkish
Packing List:
1 x ELM327 Bluetooth
Supports Car List Tips:
About Car supports list, this ELM327 works most gasoline car brand model ,but honestly we cant to test all cars one by one .

Each car brand has many series, maybe it works one brand this model, but no supports another model is possible .Like for Citroen works C3/C4,but no sure if works C5 or not.