Beijing Chenjing Electronics Co., Ltd. (formerly state-owned 707 Factory), old name: state-owned Beijing Morning Star Radio Equipment Factory. The "Chenjing" brand crystal oscillator they produce is the best crystal oscillator in my country and has been used in aerospace, military industry and other fields a long time ago. The crystal oscillator you mentioned is similar to the size of 2200uF 25V electrolytic capacitor. It should be vacuum glass (or metal) packaged. They have a wide range of varieties. The registered trademark on the crystal is 〈◇〉, a regular prism surrounded by a single square bracket.