diff --git a/src/angle.rs b/src/angle.rs
index 1733bd4..3aba55b 100644
--- a/src/angle.rs
+++ b/src/angle.rs
@@ -3,7 +3,7 @@ use core::f64::consts::pi;
 
 use funs::triganomic::{cos, sin};
 use mat::{Mat3, Mat4};
-use num::ext::Float;
+use num::kinds::Float;
 use num::cast::{NumCast, cast};
 use quat::Quat;
 use vec::Vec3;
diff --git a/src/color/color.rs b/src/color/color.rs
index 1670f86..2d811a3 100644
--- a/src/color/color.rs
+++ b/src/color/color.rs
@@ -9,7 +9,7 @@ use channel::Channel;
 use dim::{Dimensional, ToPtr};
 use funs::common::Sign;
 use num::cast::{cast, NumCast};
-use num::ext::Float;
+use num::kinds::Float;
 
 
 pub trait Color<T>: Dimensional<T>, ToPtr<T>, Eq {
diff --git a/src/funs/projection.rs b/src/funs/projection.rs
index c56e67e..4169f5a 100644
--- a/src/funs/projection.rs
+++ b/src/funs/projection.rs
@@ -2,7 +2,7 @@ use funs::triganomic::tan;
 use angle::Angle;
 use mat::Mat4;
 use num::cast::{NumCast, cast};
-use num::ext::Float;
+use num::kinds::Float;
 
 /**
  * Create a perspective projection matrix
diff --git a/src/lmath.rc b/src/lmath.rc
index 2439e38..b6c97b5 100644
--- a/src/lmath.rc
+++ b/src/lmath.rc
@@ -68,8 +68,8 @@ pub mod num {
     pub mod cast;
     #[path = "num/default_eq.rs"]
     pub mod default_eq;
-    #[path = "num/ext.rs"]
-    pub mod ext;
+    #[path = "num/kinds.rs"]
+    pub mod kinds;
     #[path = "num/rhs.rs"]
     pub mod rhs; // FIXME: see module description
 }
diff --git a/src/mat.rs b/src/mat.rs
index a2e99eb..388288c 100644
--- a/src/mat.rs
+++ b/src/mat.rs
@@ -11,7 +11,7 @@ use funs::common::*;
 use funs::exponential::*;
 use num::cast::*;
 use num::default_eq::DefaultEq;
-use num::ext::Float;
+use num::kinds::Float;
 use quat::{Quat, ToQuat};
 use vec::{NumericVector, Vec2, Vec3, Vec4};
 
diff --git a/src/num/ext.rs b/src/num/kinds.rs
similarity index 100%
rename from src/num/ext.rs
rename to src/num/kinds.rs
diff --git a/src/quat.rs b/src/quat.rs
index b32b0fc..a4a238e 100644
--- a/src/quat.rs
+++ b/src/quat.rs
@@ -13,7 +13,7 @@ use funs::triganomic::*;
 use mat::{Mat3, Mat4};
 use num::cast::*;
 use num::default_eq::DefaultEq;
-use num::ext::Float;
+use num::kinds::Float;
 use vec::Vec3;
 
 
diff --git a/src/vec.rs b/src/vec.rs
index ec7cdbc..7bd5852 100644
--- a/src/vec.rs
+++ b/src/vec.rs
@@ -10,7 +10,7 @@ use dim::{Dimensional, ToPtr};
 use funs::exponential::Exp;
 use num::cast::*;
 use num::default_eq::DefaultEq;
-use num::ext::Number;
+use num::kinds::Number;
 
 ///
 /// The base vector trait