diff --git a/specs/core/0_beacon-chain.md b/specs/core/0_beacon-chain.md
index a0001d03b..f6427f1d4 100644
--- a/specs/core/0_beacon-chain.md
+++ b/specs/core/0_beacon-chain.md
@@ -234,7 +234,7 @@ These configurations are updated for releases, but may be out of sync during `de
 | `SLOTS_PER_HISTORICAL_ROOT` | `2**13` (= 8,192) | slots | ~13 hours |
 | `MIN_VALIDATOR_WITHDRAWABILITY_DELAY` | `2**8` (= 256) | epochs | ~27 hours |
 | `PERSISTENT_COMMITTEE_PERIOD` | `2**11` (= 2,048)  | epochs | 9 days  |
-| `MAX_CROSSLINK_EPOCHS` | `2**6` (= 64) |
+| `MAX_CROSSLINK_EPOCHS` | `2**6` (= 64) | epochs | ~7 hours |
 
 * `MAX_CROSSLINK_EPOCHS` should be a small constant times `SHARD_COUNT // SLOTS_PER_EPOCH`