Ibn Abbas (رضی اللہ عنہ) said
“The Kursi is the place of Allah’s feet and the Arsh, it’s magnitude cannot be estimated”
Al Hakim recorded it in His Tafsir (2/282) from Abu Asim with this chain as a mawquf on ibn Abbas and he said “This is Sahih Hadith according to the conditions of our Shaykhain (imam Bukhari and Muslim) but they did not include it, ad dahabi agreed with them
and recorded it in his uluww which is page 102 as mawquf and he said “it’s narrators are Trustworthy”
Also, al daraqutni recorded this in Al sifat 49 from Abu Asim narrated by ibn Abi hatim in his Tafsir 2/584.