Size S: 20.8" length, total 4 sizes from 20" to 40". Suitable for MANY TYPES of PETS with different weights, please MEASURE from your dog's harness CLIP to your car's LOCK BAR to determine the best size. We believe all your demands will be satisfied. MULTI-CONNECTION: DUAL SWIVEL CLIP and ATTACHMENT LATCH, you can connect it to your car's SEAT BELT with the nap or you can connect it to the LOCK BAR in the creases of your car's back seat as an extra strap for your pet. So the PASSENGER and your PET can use the seat belt AT THE SAME TIME without influence. [Material] -- 100% STAINLESS STEEL heavy duty, rustproof and durable, Diameter -- 3mm, STRONG enough for large, ACTIVE/AGGRESSIVE dogs. [SAFETY RESTRICTION with ROOM]: Able to WITHSTAND 100KG PULL, RESTRICT your dog's ACTIVE SPACE in the car, this both avoids danger and also allows your dog to sit, stand and lie down. Wide Application: Not only can be used in your car as a SEAT BELT LEASH / ANTI-CHEW for dogs, but also can be used as