diff --git a/code/game/objects/items/holosign_creator.dm b/code/game/objects/items/holosign_creator.dm
index e92c9b2d2e..47cf6f4ba7 100644
--- a/code/game/objects/items/holosign_creator.dm
+++ b/code/game/objects/items/holosign_creator.dm
@@ -92,6 +92,14 @@
 	creation_time = 0
 	max_signs = 3
 
+/obj/item/holosign_creator/combifan
+	name = "ATMOS holo-combifan projector"
+	desc = "A holographic projector that creates holographic combi-fans that prevent changes in atmosphere and temperature conditions. Somehow."
+	icon_state = "signmaker_atmos"
+	holosign_type = /obj/structure/holosign/barrier/combifan
+	creation_time = 0
+	max_signs = 3
+
 /obj/item/holosign_creator/medical
 	name = "\improper PENLITE barrier projector"
 	desc = "A holographic projector that creates PENLITE holobarriers. Useful during quarantines since they halt those with malicious diseases."
diff --git a/code/game/objects/structures/holosign.dm b/code/game/objects/structures/holosign.dm
index 617f42ed29..9d22f669d5 100644
--- a/code/game/objects/structures/holosign.dm
+++ b/code/game/objects/structures/holosign.dm
@@ -93,6 +93,24 @@
 /obj/structure/holosign/barrier/firelock/blocksTemperature()
 	return TRUE
 
+/obj/structure/holosign/barrier/combifan
+	name = "holo combifan"
+	desc = "A holographic barrier resembling a blue-accented tiny fan. Though it does not prevent solid objects from passing through, gas and temperature changes are kept out."
+	icon_state = "holo_combifan"
+	max_integrity = 30
+	density = FALSE
+	anchored = TRUE
+	alpha = 150
+	CanAtmosPass = ATMOS_PASS_NO
+	resistance_flags = FIRE_PROOF
+
+/obj/structure/holosign/barrier/combolock/blocksTemperature()
+	return TRUE
+
+/obj/structure/holosign/barrier/combolock/Initialize()
+	. = ..()
+	air_update_turf(TRUE)
+
 /obj/structure/holosign/barrier/cyborg
 	name = "Energy Field"
 	desc = "A fragile energy field that blocks movement. Excels at blocking lethal projectiles."
diff --git a/code/modules/research/designs/autolathe_desings/autolathe_designs_construction.dm b/code/modules/research/designs/autolathe_desings/autolathe_designs_construction.dm
index a4abd6e183..c3e3993cb2 100644
--- a/code/modules/research/designs/autolathe_desings/autolathe_designs_construction.dm
+++ b/code/modules/research/designs/autolathe_desings/autolathe_designs_construction.dm
@@ -103,7 +103,17 @@
 /datum/design/rcd_ammo
 	name = "Compressed Matter Cartridge"
 	id = "rcd_ammo"
-	build_type = AUTOLATHE
-	materials = list(MAT_METAL = 12000, MAT_GLASS=8000)
+	build_type = AUTOLATHE | PROTOLATHE
+	materials = list(MAT_METAL = 12000, MAT_GLASS = 8000)
 	build_path = /obj/item/rcd_ammo
-	category = list("initial","Construction")
+	category = list("initial","Construction","Tool Designs")
+	departmental_flags = DEPARTMENTAL_FLAG_ENGINEERING
+
+/datum/design/rcd_ammo_large
+	name = "Large Compressed Matter Cartridge"
+	id = "rcd_ammo_large"
+	build_type = AUTOLATHE | PROTOLATHE
+	materials = list(MAT_METAL = 48000, MAT_GLASS = 32000)
+	build_path = /obj/item/rcd_ammo/large
+	category = list("Tool Designs")
+	departmental_flags = DEPARTMENTAL_FLAG_ENGINEERING
diff --git a/code/modules/research/designs/misc_designs.dm b/code/modules/research/designs/misc_designs.dm
index 54a7af8f8c..0059e0c417 100644
--- a/code/modules/research/designs/misc_designs.dm
+++ b/code/modules/research/designs/misc_designs.dm
@@ -403,6 +403,16 @@
 	category = list("Equipment")
 	departmental_flags = DEPARTMENTAL_FLAG_ENGINEERING
 
+/datum/design/holosigncombifan
+	name = "ATMOS Holo-Combifan Projector"
+	desc = "A holographic projector that creates holographic barriesr that prevent changes in atmospheric and temperature conditions."
+	id = "holosigncombifan"
+	build_type = PROTOLATHE
+	materials = list(MAT_METAL = 7500, MAT_GLASS = 2500, MAT_SILVER = 2500, MAT_GOLD = 2500, MAT_TITANIUM = 1750)
+	build_path = /obj/item/holosign_creator/combifan
+	category = list("Equipment")
+	departmental_flags = DEPARTMENTAL_FLAG_ENGINEERING
+
 /datum/design/forcefield_projector
 	name = "Forcefield Projector"
 	desc = "A device which can project temporary forcefields to seal off an area."
diff --git a/code/modules/research/techweb/all_nodes.dm b/code/modules/research/techweb/all_nodes.dm
index 2fa5901ec9..9556e3853b 100644
--- a/code/modules/research/techweb/all_nodes.dm
+++ b/code/modules/research/techweb/all_nodes.dm
@@ -200,7 +200,7 @@
 	display_name = "Advanced Engineering"
 	description = "Pushing the boundaries of physics, one chainsaw-fist at a time."
 	prereq_ids = list("engineering", "emp_basic")
-	design_ids = list("engine_goggles", "magboots", "forcefield_projector", "weldingmask" , "rcd_loaded", "rpd", "tray_goggles_prescription", "engine_goggles_prescription", "mesons_prescription", "rcd_upgrade_frames", "rcd_upgrade_simple_circuits")
+	design_ids = list("engine_goggles", "magboots", "forcefield_projector", "weldingmask" , "rcd_loaded", "rpd", "tray_goggles_prescription", "engine_goggles_prescription", "mesons_prescription", "rcd_upgrade_frames", "rcd_upgrade_simple_circuits", "rcd_ammo_large")
 	research_costs = list(TECHWEB_POINT_TYPE_GENERIC = 4000)
 	export_price = 5000
 
@@ -644,7 +644,7 @@
 	id = "exp_tools"
 	display_name = "Experimental Tools"
 	description = "Highly advanced construction tools."
-	design_ids = list("exwelder", "jawsoflife", "handdrill")
+	design_ids = list("exwelder", "jawsoflife", "handdrill", "holosigncombifan")
 	prereq_ids = list("adv_engi")
 	research_costs = list(TECHWEB_POINT_TYPE_GENERIC = 2750)
 	export_price = 5000
diff --git a/icons/effects/effects.dmi b/icons/effects/effects.dmi
index 51e9453087..a2fce4678f 100644
Binary files a/icons/effects/effects.dmi and b/icons/effects/effects.dmi differ