diff --git a/CHANGELOG.md b/CHANGELOG.md
index eceb84f55..81ab6a28a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@ v2.5.7 (FUTURE)
 ## Enhancements
 
 * [#2357](https://github.com/digitalocean/netbox/issues/2357) - Enable filtering of devices by rack face
+* [#2878](https://github.com/digitalocean/netbox/issues/2878) - Add cable types for OS1/OS2 singlemode fiber
 * [#2903](https://github.com/digitalocean/netbox/issues/2903) - Clarify purpose of tags field on interface edit form
 
 ## Bug Fixes
diff --git a/netbox/dcim/constants.py b/netbox/dcim/constants.py
index 22d4468fc..75a18e36f 100644
--- a/netbox/dcim/constants.py
+++ b/netbox/dcim/constants.py
@@ -355,11 +355,14 @@ CABLE_TYPE_CAT6A = 1610
 CABLE_TYPE_CAT7 = 1700
 CABLE_TYPE_DAC_ACTIVE = 1800
 CABLE_TYPE_DAC_PASSIVE = 1810
+CABLE_TYPE_MMF = 3000
 CABLE_TYPE_MMF_OM1 = 3010
 CABLE_TYPE_MMF_OM2 = 3020
 CABLE_TYPE_MMF_OM3 = 3030
 CABLE_TYPE_MMF_OM4 = 3040
 CABLE_TYPE_SMF = 3500
+CABLE_TYPE_SMF_OS1 = 3510
+CABLE_TYPE_SMF_OS2 = 3520
 CABLE_TYPE_AOC = 3800
 CABLE_TYPE_POWER = 5000
 CABLE_TYPE_CHOICES = (
@@ -377,11 +380,14 @@ CABLE_TYPE_CHOICES = (
     ),
     (
         'Fiber', (
+            (CABLE_TYPE_MMF, 'Multimode Fiber'),
             (CABLE_TYPE_MMF_OM1, 'Multimode Fiber (OM1)'),
             (CABLE_TYPE_MMF_OM2, 'Multimode Fiber (OM2)'),
             (CABLE_TYPE_MMF_OM3, 'Multimode Fiber (OM3)'),
             (CABLE_TYPE_MMF_OM4, 'Multimode Fiber (OM4)'),
             (CABLE_TYPE_SMF, 'Singlemode Fiber'),
+            (CABLE_TYPE_SMF_OS1, 'Singlemode Fiber (OS1)'),
+            (CABLE_TYPE_SMF_OS2, 'Singlemode Fiber (OS2)'),
             (CABLE_TYPE_AOC, 'Active Optical Cabling (AOC)'),
         ),
     ),