Chain size

3/8" · .050" · 66 DL chain: which saws it fits

A 3/8" (full profile) pitch, .050" gauge chain with 66 drive links. It is most often found on 18" bars, and fits 202 chainsaw and pole-saw models from 4 brands in Oregon's fitment data. Bar length alone doesn't decide fit — all three numbers have to match your saw.

Pitch3/8" (full profile)

Gauge.050"

Drive links66

Typical bar18"

Oregon chains in this size: 72EXL066G, 72EXL066X2, 72LPX066G, 72TXL066G

Popular saws that take this chain

ECHO CS-59018" bar STIHL MS 29118" bar

Confirm it's your size

Read the bar stamp. Near the tail of the guide bar you'll usually find pitch, gauge and drive links, e.g. 3/8 .050 66. Some bars stamp the Oregon bar number instead — look it up on oregonproducts.com.
Count the drive links on your old chain — the teeth that ride inside the bar groove, not the cutters. It must be exactly 66.
If the stamp is worn off, the owner's manual lists the bar and chain; find it on the manufacturer's support site.

Easy to mix up with

3/8" · .050" · 64 DL — same pitch and gauge, shorter loop (usually 18" bars)
3/8" · .050" · 68 DL — same pitch and gauge, longer loop (usually 18" bars)

All 202 models, by brand

STIHL 104 models

MS 291 18"
026 18"
26 18"
026 PRO 18"
026P 18"
028 18"
28 18"
028 Super 18"
029 18"
29 18"
030 18"
30 18"
031 18"
31 18"
032 18"
32 18"
034 18"
34 18"
034 SUPER 18"
036 18"
36 18"
036 PRO 18"
036 QS 18"
038 18"
38 18"
038 Super MAGNUM 18"
039 18"
39 18"
040 18"
40 18"
041 18"
41 18"
042 18"
42 18"
044 18"
44 18"
044 MAGNUM 18"
045 18"
45 18"
046 18"
46 18"
046 MAGNUM 18"
048 18"
48 18"
056 18"
56 18"
056 SUPER 18"
064 18"
64 18"
066 18"
66 18"
066 MAGNUM 18"
E15 18"
E20 18"
E220 18"
MS 260 18"
MS 260 Pro 18"
MS 261 18"
MS 261 C-M 18"
MS 261 C-MQ 18"
MS 261 CQ 18"
MS 270 18"
MS 270 C 18"
MS 270 C-B 18"
MS 270 CQS 18"
MS 290 18"
MS 291 C-BEQ 18"
MS 310 18"
MS 311 18"
MS 341 18"
MS 360 18"
MS 360 C 18"
MS 360 Pro 18"
MS 360 QS 18"
MS 361 18"
MS 361 C-B 18"
MS 361 QS 18"
MS 362 18"
MS 362 C-M 18"
MS 362 C-MQ 18"
MS 362 CQ 18"
MS 362 RC-M 18"
MS 390 18"
MS 391 18"
MS 400 C-M 18"
MS 440 18"
MS 440 MAGNUM 18"
MS 441 18"
MS 441 C 18"
MS 441 C-M 18"
MS 441 C-MQ 18"
MS 441 RC-M 18"
MS 460 18"
MS 460 MAGNUM 18"
MS 461 18"
MS 462 18"
MS 500i 18"
MS 650 18"
MS 660 18"
MS 660 MAGNUM 18"
MS 661 C-M 18"
MS 661 R C-M 18"
MSE 220 18"
MSE 250 C 18"

Poulan 43 models

203 18"
245 18"
306 18"
306 A 18"
330 18"
360 18"
361 18"
365 18"
375 18"
380 18"
385 18"
395 18"
400 18"
405 18"
446 18"
450 18"
455 18"
525 18"
655 18"
3350 18"
3400 18"
3450 18"
3500 18"
3600 18"
3650 18"
3700 18"
3750 18"
3800 18"
3900 18"
4000 18"
4200 18"
4400 18"
4900 18"
5200 18"
5400 18"
5500 18"
6700 18"
6900 18"
7700 18"
8500 18"
PP4818 18"
PP4818A 18"
PP4818AVX 18"

ECHO 33 models

CS-590 18"
CS-60 18"
CS-60S 18"
CS-451 18"
CS-452 18"
CS-500EVL 18"
CS-501EVL 18"
CS-510EVL 18"
CS-550 18"
CS-550EVL 18"
CS-600P 18"
CS-601 18"
CS-602 18"
CS-610T 18"
CS-620P 18"
CS-620P-18 18"
CS-620PW 18"
CS-650 18"
CS-650EVL 18"
CS-660 18"
CS-670 18"
CS-680 18"
CS-701 18"
CS-702 18"
CS-706 18"
CS-750 18"
CS-750EVL 18"
CS-800P 18"
CS-900 18"
CS-1001 18"
CS-6700 18"
CS-8000 18"
CST-610 18"

Craftsman 22 models

Source: Oregon part-finder fitment data, retrieved 2026-07-06. We list a model here when Oregon recommends a 3/8" · .050" · 66 DL chain for one of its bar lengths; we haven't fitted each saw ourselves. Some bar configurations in the source don't give a drive-link count and aren't included — if your saw isn't listed, count your chain.