Sierra 18-720-4000 T-Bolt Band Clamp | 4 in. Exhaust Hose | 316 SS

Sierra 18-720-4000 — T-Bolt Band Clamp | 4 in. Exhaust Hose | Marine Grade 316 Stainless Steel | Below Waterline Rated

Sierra 18-720-4000 is a marine-grade 316 stainless steel T-bolt band clamp designed specifically for 4 in. ID Shields 200 and 250 series marine exhaust hose. Features an extra-long 1/4 in. bolt with nyloc nut, 0.25 in. band thickness, and 3/4 in. band width. Diameter range 4.18–4.84 in. Rated for below waterline applications. Maximum torque 75 in-lbs. Sold individually — order the quantity needed.

Confirm Fitment Before Ordering

Not sure if this clamp fits your hose? Give us your hose size, series, and application and we’ll confirm it for you before you order — by email, text, or live chat.

Part Specifications

• Sierra Part Number: 18-720-4000
• Type: T-bolt band clamp
• Application: 4 in. ID Shields 200 and 250 series marine exhaust hose
• Diameter Range: 4.18–4.84 in.
• Material: Marine grade 316 stainless steel
• Bolt: Extra-long 1/4 in. bolt with nyloc nut
• Band Thickness: 0.25 in.
• Band Width: 3/4 in.
• Maximum Torque: 75 in-lbs
• Rated For: Below waterline applications
• Sold As: Individually — order quantity as needed
• Vendor: Sierra International

Additional Information

• Vendor: Sierra International
• Part Number: 18-720-4000
• Application: 4 in. ID Shields 200 and 250 series marine exhaust hose
• Sold As: Individually

Installation Notes

Install following the hose and fitting manufacturer’s guidelines for your exhaust system. Torque to a maximum of 75 in-lbs — do not over-torque. Confirm the clamp diameter range (4.18–4.84 in.) covers your installed hose outside diameter before installation.

Frequently Asked Questions

Q: What hose is this clamp designed for?
A: Sierra 18-720-4000 is designed specifically for 4 in. ID Shields 200 and 250 series marine exhaust hose. It covers a diameter range of 4.18–4.84 in. Confirm your hose outside diameter falls within this range before ordering.

Q: Why use a T-bolt clamp instead of a standard worm gear clamp on exhaust hose?
A: T-bolt clamps apply uniform clamping pressure around the entire hose circumference, which is important for large-diameter exhaust hose connections subject to heat cycling, vibration, and pressure. Standard worm gear clamps concentrate force at the screw point and can allow leaks on large marine exhaust applications. T-bolt clamps are the correct type for Shields 200/250 series exhaust hose.

Q: Is this clamp rated for below waterline use?
A: Yes — the 18-720-4000 is specifically rated for below waterline applications. The 316 stainless steel construction resists corrosion in both salt and fresh water environments.

Q: What is the maximum torque for this clamp?
A: Maximum torque is 75 in-lbs. Do not exceed this value — over-torquing can distort the hose or damage the clamp band.

Q: How many clamps do I need?
A: This listing is for one (1) individual clamp. Order the quantity needed for your installation — typically two clamps per hose connection (one at each end).