Belt No. (inch)
code	Internal length(mm)	code	Internal length(mm)	code	Internal length(mm)	code	Internal length(mm)	code	Internal length(mm)	code	Internal length(mm)
20	1800	20	1950	20	2200	20	2600	20	3150	20	3550
20	1875	20	2000	20	2240	20	2650	20	3250	20	3650
20	1900	20	2050	20	2360	20	2800	20	3350	20	3750
20	1925	20	2120	20	2500	20	3000	20	3450	20	4000