Sea Gull 海鸥 is a Tianjin Watch Factory brand, but this one (without the hyphen) is a product of Shanghai, probably the Shanghai Watch Factory. Shanghai Sea Gulls are seen more often with the pinyin name Haiou. The English-branded example is a rare watch. 7524 is also a model number of export-intended Budlet/Chunlei watches. The second hand and the Shanghai crown may or may not be original to the watch. Under the balance: SAH above SZ1.