diff --git a/Sources/kvSIMD/KvQuaternions.swift b/Sources/kvSIMD/KvQuaternions.swift
index 1671574..22aedbb 100644
--- a/Sources/kvSIMD/KvQuaternions.swift
+++ b/Sources/kvSIMD/KvQuaternions.swift
@@ -30,7 +30,7 @@ import Foundation
 /// A `Float`-element quaternion.
 ///
 /// It's represented as a 4-element vector where first three elements are a vector (imaginary) part, fourth element is a scalar (real) part.
-public struct simd_quatf : Equatable, CustomDebugStringConvertible {
+public struct simd_quatf : Equatable, Sendable, CustomDebugStringConvertible {
 
     /// A 4-element vector representation of a quaternion where first three elements are a vector (imaginary) part, fourth element is a scalar (real) part.
     public var vector: simd_float4
@@ -326,7 +326,7 @@ public struct simd_quatf : Equatable, CustomDebugStringConvertible {
 /// A `Double`-element quaternion.
 ///
 /// It's represented as a 4-element vector where first three elements are a vector (imaginary) part, fourth element is a scalar (real) part.
-public struct simd_quatd : Equatable, CustomDebugStringConvertible {
+public struct simd_quatd : Equatable, Sendable, CustomDebugStringConvertible {
 
     /// A 4-element vector representation of a quaternion where first three elements are a vector (imaginary) part, fourth element is a scalar (real) part.
     public var vector: simd_double4