Resistor 100K Ohm 5% 0,25W 1/4W

It has an ATMega32U4 chip running at 16Mhz with a factory-loaded bootloader. It does not include pins so we can solder only the pins we need. Characteristic: - Microcontroller: ATmega32U4
- Operation: 5V
- Power (max): 5-12V
- Total I / O pins: 20
- PWM pins: 5
- Analog pins: 12
- Maximum current of I / O pins: 40 mA
- Maximum current of pin 3.3V: 50 mA
- Flash memory: 32 KB (4 KB used by the bootloader)
- SRAM: 2.5 KB
- EEPROM: 1 KB
- Speed: 16 MHz
- external interrupt
- TWI / I2C, UART, SPI interfaces
- Dimensions: 18x33mm
- Weight: 30 grams

Includes a switch to output the voltage built into the case itself.
It has a cover for protect the batteries.
The cover has perforation in case you want to secure it with a screw (not included).
Characteristic:
- Cable 12cm long
- Measures 70x 65x 18mm
- Battery length max 50mm
- Compatible batteries (LR06, R06, MN1500, AM3, UM3, HP7)

Resistor 1M Ohm 5% 0,25W 1/4W features:
-1M Ohm
-Type: Carbon film
-Tolerance: ±5%
-Power: 0.25W
-Dimensions: 2x7mm

Rechargeable battery 9V 6F22 Ni-MH 250 mAh Ready to Use features:

10x Photoresistor 5mm GL5516 LDR 5-10k for Arduino.
Photoresistor is a resistor whose resistance decreases when increasing the intensity of the light that falls on it. 10x Photoresistor GL5516 LDR features:
- Model: GL5516
- Spectral peak: 540nm
- Maximum DC voltage: 150V
- Maximum power: 90mW.
- Resistance with light (10lux): 5-10KΩ
- Resistance with darkness (0lux): 0.5MΩ
- Response time: 20ms
- Operating temperature: -30ºC - 70ºC

The DIP switch type THT (4 rows 8 Pins) with a pitch of 2.54mm / 0.1 ". It works with the current of 50mA DC 12V.

High sensitivity to Ammonia (NH3), Nitrogen oxides (NOx), Alcohol, Sulphides, Benzene (C6H6), CO2, smoke and other harmful gases.  The MQ-135 sensor is to sensible for other gasses in the air so that is not possible to get good values for CO2 from it.
MQ-135 Air Quality Sensor features:
- Main chip: MQ-135 natural gas sensor and comparator LM393
- Working voltage: 5V
- Current: 150mA
- Digital output: TTL 0/1
- Analog output: analog voltage sensing value
- Quick response features:
- Detection concentration:
   10ppm - 300ppm NH3
   10ppm - 1000ppm Benzene
   10ppm - 300ppm Alcohol
- Adjustable sensitivity with the potentiometer
- Size: 32mm x 20mmx 18mm

Potentiometer B20K linear features:
-20k OHM kΩ - linear potentiometer 20k Arduino
-Tolerance: +/- 20%
- Power: 0.125W