diff --git a/README.md b/README.md
index d5126f8..2a674d0 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,6 @@
 # two_pole_dc_pass
 
-Implements the old 7/8ths LAG filter but squared.
-i.e. two pole version
+Implements the old 7/8ths LAG filter but squared and a 15/16 squared lag filter
+i.e. two pole versions.
+
+Optimised for 8 bit implementations.