diff --git a/sync.go b/sync.go
index 825de99..bf38c16 100644
--- a/sync.go
+++ b/sync.go
@@ -10,7 +10,9 @@ import (
 // in case of two used disks per write (RAID 1, 5) and queue depth of 2,
 // 16 concurrent Sync calls should be able to saturate 16 HDDs RAID
 //TODO: benchmark it out, maybe provide tweak parmeter
-var syncSemaphore chan struct{} = make(chan struct{}, 16)
+const SyncThreadsMax = 16
+
+var syncSemaphore chan struct{} = make(chan struct{}, SyncThreadsMax)
 
 func syncDir(dir string) error {
 	if runtime.GOOS == "windows" {