diff --git a/src/ResearchTree/NodeIDs.h b/src/ResearchTree/NodeIDs.h
index fdec6e8..b99eeb9 100644
--- a/src/ResearchTree/NodeIDs.h
+++ b/src/ResearchTree/NodeIDs.h
@@ -85,12 +85,12 @@ enum EngineIDs: Int {
 
 enum OSIDs: Int {
     // Tier 1
-    NeuralOS = 300010,
-    ExoSkelOS,
-    Shields1,
-    Enhancements1,
-    FuelSave1,
-    LongRange1,
+    NeuralOS      = 300010,
+    ExoSkelOS     = 300030,
+    Shields1      = 400010,
+    Enhancements1 = 400050,
+    FuelSave1     = 400051,
+    LongRange1    = 400030,
 
     // Tier 2
     SparkOS,
diff --git a/src/ResearchTree/ResearchTree.cpp b/src/ResearchTree/ResearchTree.cpp
index 22653ca..db2dbba 100644
--- a/src/ResearchTree/ResearchTree.cpp
+++ b/src/ResearchTree/ResearchTree.cpp
@@ -334,10 +334,33 @@ void ResearchTree::generateOSTree() {
         return;
     }
 
+    // T1
     _osNodes.emplace(NeuralOS, Node{Node::Type::OS, "Neural OS", 1, 3,
                                     "Synchronise the links between your nervous system and the M.A.S.S. perfectly.",
                                     "Accuracy +24, Shield +624, Fuel burn rate +200, Magazine reload +24, Energy recharge +66, Shield recover +1620",
                                     "Shield +3%"});
+    _osNodes.emplace(ExoSkelOS, Node{Node::Type::OS, "ExoSkel OS", 1, 3,
+                                     "An OS that simulates the M.A.S.S. as your exoskeleton.",
+                                     "Accuracy +45, Shield +360, Fuel burn rate +300, Magazine reload +30, Energy recharge +83, Shield recover +608",
+                                     "Accuracy +3%"});
+    _osNodes.emplace(Shields1, Node{Node::Type::Module, "Shields 1", 1, 0,
+                                    "Module that helps in optimising shield usage.",
+                                    "Shield +60, Fuel burn rate +25, Shield recover +506", ""});
+    _osNodes.emplace(Enhancements1, Node{Node::Type::Module, "Enhancements 1", 1, 0,
+                                         "An overall enhancement module.",
+                                         "Accuracy +1, Shield +36, Magazine reload +13, Energy recharge +16, Fuel burn rate -3, Shield recover +169", ""});
+    _osNodes.emplace(FuelSave1, Node{Node::Type::Module, "Fuel Save 1", 1, 0,
+                                     "Optimisation module for energy usage of the M.A.S.S. frame.",
+                                     "Fuel burn rate -5, Fuel recharge +2", ""});
+    _osNodes.emplace(LongRange1, Node{Node::Type::Module, "Long Range 1", 1, 0,
+                                      "Controlling module that helps in stabilisation for higher accuracy and reload speed.",
+                                      "Accuracy +2, Fuel burn rate +50, Magazine reload +25, Energy recharge +33", ""});
+
+    _osNodes.at(NeuralOS).addChild(_osNodes.at(Shields1));
+    _osNodes.at(NeuralOS).addChild(_osNodes.at(Enhancements1));
+    _osNodes.at(NeuralOS).addChild(_osNodes.at(ExoSkelOS));
+    _osNodes.at(ExoSkelOS).addChild(_osNodes.at(FuelSave1));
+    _osNodes.at(ExoSkelOS).addChild(_osNodes.at(LongRange1));
 
     _osNodes.at(NeuralOS).setState(Node::State::Unlocked);
 }