Long 75 !
All in all this, as we might expect, is sturdy robust and beautifully engineered. My weedy muscles meant I had to employ one or two tricks to insert it correctly but it fits the 50mm diameter German rotary clothes lines perfectly and would also allow one to move it should the need arise, which is what I suspect most owners would prefer rather than fixing thee whole thing in concrete. I would say that if you have a compatible rotary drier ( can also be used for umbrellas as well ) , then it's essential.