New #05007300 OEM Gravely Zero-Turn Mower ZT-HD SeatONE NEW GRAVELY HD SEAT. The item “New #05007300 OEM Gravely Zero-Turn Mower ZT-HD Seat” is in sale since Tuesday, April 9, 2019. This item is in the category “Home & Garden\Yard, Garden & Outdoor Living\Outdoor Power Equipment\Snow Blowers”. The seller is “bgdriver” and is located in.