Modular Marble Drop Blocks

Create an infinite number of marble tracks with interconnecting blocks! Designed to work with 7mm steel ball bearing there should be one in your spare parts bag if you built the kit mk3s but has been tested to work with steel ball bearings as small as 5mm these are the size of most magnetic buckyball toys if you have those on hand . You can also scale the print to fit larger or smaller bearings with no ill effect.