diff --git a/src/clients/hyper_client.rs b/src/clients/hyper_client.rs
index dfdd16c1..3f4c0fd7 100644
--- a/src/clients/hyper_client.rs
+++ b/src/clients/hyper_client.rs
@@ -25,6 +25,13 @@ impl Default for HyperWebPushClient {
     }
 }
 
+impl From<Client<HttpsConnector<HttpConnector>>> for HyperWebPushClient {
+    /// Creates a new client from a custom hyper HTTP client.
+    fn from(client: Client<HttpsConnector<HttpConnector>>) -> Self {
+        Self { client }
+    }
+}
+
 impl HyperWebPushClient {
     /// Creates a new client.
     pub fn new() -> Self {
diff --git a/src/clients/isahc_client.rs b/src/clients/isahc_client.rs
index d4c67947..5b8dec2b 100644
--- a/src/clients/isahc_client.rs
+++ b/src/clients/isahc_client.rs
@@ -26,6 +26,13 @@ impl Default for IsahcWebPushClient {
     }
 }
 
+impl From<HttpClient> for IsahcWebPushClient {
+    /// Creates a new client from a custom Isahc HTTP client.
+    fn from(client: HttpClient) -> Self {
+        Self { client }
+    }
+}
+
 impl IsahcWebPushClient {
     /// Creates a new client. Can fail under resource depletion.
     pub fn new() -> Result<Self, WebPushError> {
diff --git a/src/message.rs b/src/message.rs
index bff20d49..8a1ff419 100644
--- a/src/message.rs
+++ b/src/message.rs
@@ -208,5 +208,5 @@ impl<'a> WebPushMessageBuilder<'a> {
 }
 
 fn is_base64url_char(c: char) -> bool {
-    return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || (c == '-' || c == '_');
+    c.is_ascii_uppercase() || c.is_ascii_lowercase() || c.is_ascii_digit() || (c == '-' || c == '_')
 }
diff --git a/src/vapid/mod.rs b/src/vapid/mod.rs
index b8366d59..9fbf7d72 100644
--- a/src/vapid/mod.rs
+++ b/src/vapid/mod.rs
@@ -2,7 +2,6 @@
 
 pub use self::builder::VapidSignatureBuilder;
 use self::key::VapidKey;
-pub use self::signer::Claims;
 pub use self::signer::VapidSignature;
 use self::signer::VapidSigner;