THE BLOCK TURNS AND LOCKS DOWN LIKE IT SHOULD. THE MOUNT HOLES ON THE BOTTOM ARE 3 1/8 APART O. THE CENTER STUD IS 1 5/8 X 1/8H APPROX. THE DISTANCE FROM THE BOTTOM OF THE BASE PLATE TO THE CENTER OF THE SLOT FOR THE TOOL HOLDER IS 2 3/4 APPROX. THE SLOT FOR THE TOOL IS 11/16 APPROX. THERE ARE A COUPLE RUSTY SPOTS ON IT THE ASSEMBLY. ONE SET SCREWS IS MISSING ON THE BLOCK. THERE ARE MEASUREMENTS IN THE PICTURES. CHECK OUT MY OTHER LISTINGS. NO WARRANTIES GIVEN OR IMPLIED. ALL ITEMS MUST BE PAID FOR WITHIN 5 DAYS FROM THE END OF THE LISTING. NO EXCEPTIONS; NO MATTER HOW ...