diff --git a/src/class.rs b/src/class.rs
index 6a786b1..ad13809 100644
--- a/src/class.rs
+++ b/src/class.rs
@@ -2,7 +2,7 @@ use core::convert::TryFrom;
 use core::time::Duration;
 
 use interchange::Requester;
-use apdu_dispatch::types::ContactInterchange;
+use apdu_dispatch::interchanges;
 
 use crate::{
     constants::*,
@@ -33,7 +33,7 @@ where
 {
     pub fn new(
         allocator: &'static UsbBusAllocator<Bus>,
-        request_pipe: Requester<ContactInterchange>,
+        request_pipe: Requester<interchanges::Contact>,
     ) -> Self {
         let read = allocator.bulk(PACKET_SIZE as _);
         let write = allocator.bulk(PACKET_SIZE as _);
diff --git a/src/pipe.rs b/src/pipe.rs
index 6ea74ec..50c6285 100644
--- a/src/pipe.rs
+++ b/src/pipe.rs
@@ -1,6 +1,6 @@
 use core::convert::TryFrom;
 
-use apdu_dispatch::types::ContactInterchange;
+use apdu_dispatch::interchanges;
 use interchange::Requester;
 use interchange::Interchange;
 
@@ -53,7 +53,7 @@ where
     // pub(crate) rpc: TransportEndpoint<'rpc>,
     seq: u8,
     state: State,
-    interchange: Requester<ContactInterchange>,
+    interchange: Requester<interchanges::Contact>,
     sent: usize,
     outbox: Option<RawPacket>,
 
@@ -71,7 +71,7 @@ where
 {
     pub(crate) fn new(
         write: EndpointIn<'static, Bus>,
-        request_pipe: Requester<ContactInterchange>,
+        request_pipe: Requester<interchanges::Contact>,
     ) -> Self {
 
         assert!(MAX_MSG_LENGTH >= PACKET_SIZE);
diff --git a/src/types.rs b/src/types.rs
index 9704304..1c95780 100644
--- a/src/types.rs
+++ b/src/types.rs
@@ -1,14 +1,11 @@
 // use cortex_m_semihosting::hprintln;
-use heapless_bytes::Bytes;
-
-use crate::constants::*;
 use core::time::Duration;
 
 // pub mod apdu;
 pub mod packet;
 pub mod tlv;
 
-pub type MessageBuffer = Bytes<MAX_MSG_LENGTH_TYPE>;
+pub type MessageBuffer = apdu_dispatch::interchanges::Data;
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub enum ClassRequest {