We suggest changing your ribbons after replacing 3 paper tape rolls. This universal twin-spool ribbon is compatible with all printing calculators that take ribbon spools, including popular brands such as Canon, Casio, Innovera, Monroe, Sharp, and Victor.
Here are some of the brands and models these ribbons are compatible in:

Addo - X P-14, 9212
Adler - 12P, 121P, 121PD, 1410P, 1410PD, 120P, 120PD, 1200, 1210 and 1414
Burroughs - 3000, 6000, EA-2100, 4000, 4600, C-6453/6460, S-600, S-690, C-2050, C-2400, C-2439
Canon - 20, CP-1008, EPC-10, CP-1011D, CP-1200-1212, CP-1230D, CP-1231D, CP-1240
Casio - DL-210/220/250, DR-1210, 1212, 1410, 1411, 6210P, 6220P, DR250HD, MP41DH, R-1001/1203, DL-300/310/320, R-1/12/120, 63ER
Facit - 1175, 1177, 1190, 1191, 2201, 2204, 2251, 2252, 2257, 2259, 2202, 2253; Hermes 1000, 1100, 4200; HP 46, 81, 9805
Olympia - CPD-7220, EC-1195/3000/4000/6000/7000
Quill QX-714, P714, P712D, P713D
Royal - 100P, 300P, 300PD, 1410P, 1410PD, 12PR, 420PD, 435PD, 350PD, 960PD, 1428PD
Sharp - 300, 300 Srs, 500, 600 Srs, 742, 743, 823, 824, CS-1181/1606/1780, CS-2053/2062/2137/2157, EL-1630, VX-1612/1652/2650, 3300, 3800, EL-2630/2630GII
TI - 5200, 5213, 5215, 5217, 5219, 5320, 5330, 5340, 5660
Victor - 100, 350, 600 Series, 800 Series, 332, 1280, 1520, 1530, 1600, 1670, 1675, 1645, 1655
The manufacturer of this product is General Ribbon Company. These ribbons are made to the highest specifications and are the darkest inked universal ribbons on the market today.