This fits your. Make sure this fits by entering your model number. Aladdin Lox-On Chimney. Fits Models 12, A, B, C, 21, 21C, & 23. (Aladdin #R103). Measures 2 5/8 inch by 12 3/4 inch height and 3 inch bulge. Logo subject to change by the Aladdin Company. Borosilicate Glass All glass chimneys will vary in thickness due to the manufacturing process. They will fit the holder/burner specified in their description.