Easywisdom 30 PCS 3/4"(20mm) Black Side Release Whistle Buckles for Backpacks Strap with Free Cable Organizer Package includes 30pcs 3/4''(20mm) inch buckles.Fit for 3/4'' strap. Great for hundreds of uses belts, backpacks, straps and much more High quality with whistle. Quick release and secure lock. Dimensions: 2.17" x 1.26" x0.4'' Its design is scientific and reasonable.The buckle is secure and stuffed.