diff --git a/scrapy/core/downloader/__init__.py b/scrapy/core/downloader/__init__.py
index 4f7ab594f..f680b9082 100644
--- a/scrapy/core/downloader/__init__.py
+++ b/scrapy/core/downloader/__init__.py
@@ -83,6 +83,7 @@ class Downloader:
         self.middleware = DownloaderMiddlewareManager.from_crawler(crawler)
         self._slot_gc_loop = task.LoopingCall(self._slot_gc)
         self._slot_gc_loop.start(60)
+        self.per_slot_settings = self.settings.getdict('PER_SLOT_SETTINGS', {})
 
     def fetch(self, request, spider):
         def _deactivate(response):
@@ -99,9 +100,13 @@ class Downloader:
     def _get_slot(self, request, spider):
         key = self._get_slot_key(request, spider)
         if key not in self.slots:
-            conc = self.ip_concurrency if self.ip_concurrency else self.domain_concurrency
+            conc = self.per_slot_settings.get(key,{}).get('concurrency', self.ip_concurrency if self.ip_concurrency else self.domain_concurrency)
             conc, delay = _get_concurrency_delay(conc, spider, self.settings)
-            self.slots[key] = Slot(conc, delay, self.randomize_delay)
+            delay = self.per_slot_settings.get(key,{}).get('delay', delay)
+            randomize_delay = self.per_slot_settings.get(key, {}).get('randomize_delay', self.randomize_delay)
+            new_slot = Slot(conc, delay, randomize_delay)
+            self.slots[key] = new_slot
+
 
         return key, self.slots[key]