diff --git a/Cargo.lock b/Cargo.lock
index 28d6326..560759f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -829,7 +829,7 @@ dependencies = [
 
 [[package]]
 name = "foundation-api"
-version = "1.5.0"
+version = "1.6.0"
 dependencies = [
  "anyhow",
  "bc-components",
diff --git a/api/Cargo.toml b/api/Cargo.toml
index 88a8e06..fd8ba41 100644
--- a/api/Cargo.toml
+++ b/api/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "foundation-api"
-version = "1.5.0"
+version = "1.6.0"
 edition = "2021"
 description = "Foundation API using Gordian Sealed Transaction Protocol (GSTP)."
 authors = ["Wolf McNally, Blockchain Commons, Foundation Devices"]
diff --git a/api/src/api/bitcoin.rs b/api/src/api/bitcoin.rs
index 4e49010..d0cf146 100644
--- a/api/src/api/bitcoin.rs
+++ b/api/src/api/bitcoin.rs
@@ -8,7 +8,7 @@ pub struct SignPsbt {
     #[n(0)]
     pub account_id: String,
     #[n(1)]
-    pub psbt: String,
+    pub psbt: Vec<u8>,
 }
 
 #[quantum_link]
@@ -24,5 +24,5 @@ pub struct BroadcastTransaction {
     #[n(0)]
     pub account_id: String,
     #[n(1)]
-    pub psbt: String,
+    pub psbt: Vec<u8>,
 }