The FT90R is a digital micro servo that has been built by FEETECH specifically for continuous rotation, offering an inexpensive and easy way to get your small turret spinning or miniature robot moving, especially when paired with 60×8mm wheels designed specifically for this servo. 

These universal aluminum mounting hubs allow you to mount custom wheels and mechanisms to 8 mm diameter motor shafts. The set includes two hubs, four M3 set screws for securing the hubs to motor shafts, and one 1.5 mm Allen wrench for use with the set screws.

Module with 5 QTRX type optocoupler with analog output. The module operates from 2.9 V to 5.5 V, detects objects at a distance of up to 40 mm. The sensor will be used in projects that require detection of changes in the ground, e.g. in linefollower robots. Pololu 4445

The Tic T825 USB Multi-Interface Stepper Motor Controller makes basic control of a stepper motor easy, with quick configuration over USB using our free software. The controller supports six control interfaces: USB, TTL serial, I²C, analog voltage (potentiometer), quadrature encoder, and hobby radio control (RC).

Module with 9 QTR type optocoupler with RC (digital) output. The module operates from 2.9 V to 5.5 V, detects objects at a distance of up to 40 mm. The sensor will be used in projects that require detection of changes in the ground, e.g. in linefollower robots. Pololu 4109

Module with 6 QTR type optocoupler with RC (digital) output. The module operates from 2.9 V to 5.5 V, detects objects at a distance of up to 40 mm. The sensor will be used in projects that require detection of changes in the ground, e.g. in linefollower robots. Pololu 4106

Step-Down converter D36V28F3 with an output voltage of 3.3 V, an input voltage from 4.5 to 50 V and a maximum output current of 4.5 A. Pololu 3781

Module with 6 QTR type optocoupler with analog output. The module operates from 2.9 V to 5.5 V, detects objects at a distance of up to 40 mm. The sensor will be used in projects that require detection of changes in the ground, e.g. in linefollower robots. Pololu 4206

Module with 11 QTR type optocoupler with analog output. The module operates from 2.9 V to 5.5 V, detects objects at a distance of up to 40 mm. The sensor will be used in projects that require detection of changes in the ground, e.g. in linefollower robots. Pololu 4211

The VM-CLAP1 Hand Clap Sensor from Verbal Machines is a low-power, microprocessor-based audio sensor that can detect hand claps or finger snaps while ignoring background noises such as human speech or music. Pololu 2580

Step-Down converter D36V28F6 with an output voltage of 6 V, an input voltage from 6.3 to 50 V and a maximum output current of 4 A. Pololu 3783

A set for building a balancing robot. It has a board with an ATmega 32u4 microcontroller, engine controllers, modules with quadrature encoders and an IMU system (gyroscope, accelerometer, magnetometer). Pololu 3575

Module with 11 QTRX type optocoupler with RC (digital) output. The module operates from 2.9 V to 5.5 V, detects objects at a distance of up to 40 mm. The sensor will be used in projects that require detection of changes in the ground, e.g. in linefollower robots. Pololu 4311

Module with 11 QTRX type optocoupler with analog output. The module operates from 2.9 V to 5.5 V, detects objects at a distance of up to 40 mm. The sensor will be used in projects that require detection of changes in the ground, e.g. in linefollower robots. Pololu 4411

Module with 6 QTR type optocoupler with analog output. The module operates from 2.9 V to 5.5 V, detects objects at a distance of up to 40 mm. The sensor will be used in projects that require detection of changes in the ground, e.g. in linefollower robots. Pololu 4246

Step-Down converter D36V50F3 with an output voltage of 3.3 V, an input voltage from 4.5 to 50 V and a maximum output current of 9.5 A. Pololu 4090

Stepper motor driver based on TB67S249FTG. It allows you to control a stepper motor with voltage from 10 to 47V, with a maximum current of 1.8A. The controller can be controlled using: USB, Serial TTL, I2C, RC (PWM modeling), analog input or quadrature encoder. Pololu 3138

The S9V11MACMA switching step-up/step-down regulator efficiently produces a finely adjustable output between 2.5 V and 9 V whether it is higher or lower than the input voltage, which can range from 3 V to 16 V. The regulator also has a precision-adjustable low-voltage cutoff with hysteresis that can be used to prevent battery over-discharge.

Module with 3 QTRX type optocoupler with analog output. The module operates from 2.9 V to 5.5 V, detects objects at a distance of up to 30 mm. The sensor will be used in projects that require detection of changes in the ground, e.g. in linefollower robots. Pololu 4443

The FS5103B is a general-purpose, low-cost standard analog servo from FEETECH. Two ball bearings help reduce friction and improve performance. Servo horns and associated hardware are included.
Key specs at 6 V: 0.16 sec/60°, 53 oz-in (3.8 kg-cm), 40 g.