Z-180 3k
A102
Question is too vague as ther are more than one size deck.
what size is the belt for a 46 in cut deck belt with 6 pulley's.
43
Most LT12H mowers take a #213676 OEM belt or #6885 Gates belt for the blade application
Hard to answer without a deck size.
The size of the deck belt for the Gilson deck model 63684 is typically 1/2 inch by 83 inches. However, it's always best to consult the owner's manual or manufacturer's specifications for the most accurate information regarding replacement parts.
a115 for triple deck
5/8 x 57"
Gates
somewhere in the 44" size but best to look on the belt for a number or remove it and match it to a new belt. might also measure around around the pulleys with a small rope/string if you don't have a old belt to get the size of the belt.