Look carefully at the pictures. Basically you buy a separately packaged breadboard and a drilled piece of plastic with a few screws, standoffs and nuts. The photos show two different ways to use the racks. I tried it like this, half and half (two screws in one direction and two screws in the other). I found that I couldn't attach the board to the plastic panel with the screws facing down, which I think would be preferable as the standoffs aren't long enough to reach the nuts underneath, so I used the screws facing up , but so, I found there was only enough room for one not on top of the board (Arduino Uno, but that seems sure enough. For the money (cheap) I'm glad I bought this.
π MCIGICM 2 Channel DC 5V Relay Module: Optocoupler Low Level Trigger Expansion Board for Arduino UNO R3, DSP, ARM, PIC, AVR, STM32, Raspberry Pi
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LAFVIN Super Starter Kit for Arduino R3 Mega2560 Mega328 Nano with Detailed Tutorial - Compatible with Arduino IDE
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Gikfun Screw Shield Expansion Board: Enhance Arduino UNO R3 with the EK7007 Add-On
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MacBook Retina 13-inch (A1425, A1502) and π© 15-inch (A1398) Bottom Case Screw Set with Pentalobe Screwdriver
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π§ Premium Repair Replacement Screws & Tools for MacBook Pro Retina 15"/13" - Complete Bottom Case Set
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uxcell 3.5" HDD Screw Black 200pcs for Computer PC Case - Flat Phillips Head - 6#-32 - Hard Drive Fasteners
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π₯οΈ Helifouner 450-Piece Computer Standoffs Spacer Screws Kit: Ideal for Hard Drive, Motherboard, Fan, Power Graphics & Computer Cases
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