Set of Impractical Bolts 1: Eccentric, Double Headed, And Parallel Rings
Cold Rolled Steel    
2013
Dimensions Variable (Max height is 2 3/4")

Set of Impractical Bolts 2: Tapered
Cold Rolled Steel
2014
3/4" X 1/2" x 1/2" - 5" x 4" x 4"
Three tapered bolts ranging in size that are impossible to thread a nut onto.

Set of Impractical Bolts 3: Elongation
Cold Rolled Steel
2015
3/4" 10 TPI Elongated by xx%, xx%, xx%, and xx% 
One National Course Thread bolt and 4 iterations of elongation.

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