Hardware UNISTRUT P2350 4 WHEEL TROLLY FOR 1 5/8 OUTSIDE TRACK WIDTH x 1 1/2 MIN
1 5/8 HIGH UNISTRUT SHOWN. THE WHEELS OF THIS TROLLY WILL FIT INTO A 1 1/2 HIGH UNISTRUT, NO LESS. ON A 1 5/8 UNISTRUT THE UNDERNEATH LIP VERTICAL LENGTH = 9/32 =. 281. THEREFORE, THE MINIMUM HEIGHT UNISTRUT MUST BE AT LEAST 1 1/2.