Numerous modern mandolin makers build instruments that largely replicate the Gibson F-5 Artist models built in the early 1920s under the supervision of Gibson acoustician Lloyd Loar. Original Loar-signed instruments are sought after and extremely valuable. Other makers from the Loar period and earlier include Lyon and Healy, Vega and Larson Brothers. Some notable modern American carved mandolin manufacturers include, in addition to Kay, Gibson, Weber, Monteleone and Collings. Mandolins from other countries include The Loar (China), Santa, Rosa (China), Michael Kelly (Korea), Eastman (China), Kentucky (China), Heiden (Canada), Gilchrist (Australia) and Morgan Monroe (China).