ROBLOCK Trailer Jack Blocks 6" High 4‑Pack — Stackable RV Stabilizer Blocks with Bag, 11.5" Footprint

These ROBLOCK jack blocks are molded from a high-performance polymer with UV-resistant additives so they stand up to grime, oil and sun exposure during long-term outdoor use. Each block supports up to 40,000 lbs GVW, stacks for custom height, and fits a wide range of jack feet — from round 5th-wheel pads to scissor-style stabilizers and standard tongue jacks. The kit includes four 6-inch blocks plus a storage bag and rope handle to make transporting and storing them fast and tidy.

How do these blocks stop trailer movement and sway?

By providing a solid, wide platform under jack feet and stabilizers, the ROBLOCK units remove play between the ground and your RV, drastically reducing bounce and lateral motion. Their textured top and broad base distribute weight evenly to prevent sinking on soft surfaces.

• Large 11.5" x 11.5" footprint prevents side-to-side shifting
• Textured contact surface locks jack feet in place
• High-load polymer resists compression under weight
• Stackable design lets you fine-tune height and pressure distribution

Will these blocks work with my trailer’s jack or stabilizer?

Yes — ROBLOCK blocks are designed to accept nearly any jack foot profile, including round 5th-wheel hydraulic pads, square and circular tongue jack feet, wheel jacks and scissor stabilizers. The broad top and recessed center give a secure seat for various shapes while the robust build resists deformation under heavy loads.

• Compatible with 9" round 5th-wheel hydraulic jack feet
• Fits round, square and flat tongue jack pads and wheel jacks
• Works with scissor jacks and many aftermarket stabilizers
• 4-piece set allows placement at multiple support points

How do I adjust height and carry or store these blocks?

Each block stacks securely on another so you can add or remove layers to reach the height you need for leveling. For transport and storage, the blocks include a side hole for threading the supplied rope and a compact storage bag that keeps the set together and out of the way when not in use.

• Stackable sections let you build the exact support height
• Side hole accepts rope for easy lifting or anchoring
• Includes a compact bag for tidy storage and transport
• Lightweight polymer construction simplifies handling

What are the key size and performance specs I should know?

Each block measures roughly 6 inches tall with an overall length and width of about 11.5 inches, giving a stable platform for most RV jack feet. The manufacturer rates each block to support a GVW of up to 40,000 pounds, making them suitable for heavy trailers and fifth wheels when used as intended.

• Block height: approximately 6 inches
• Footprint: about 11.5" long x 11.5" wide
• Load capacity: 40,000 lbs GVW per block
• Set includes 4 blocks, rope and storage bag

Who is this for: The ROBLOCK 6" 4-piece trailer jack block set is ideal for RV owners, fifth-wheel travelers, and campers who need a durable, portable solution for leveling and stabilizing on uneven or soft ground. If you want a lightweight, UV-resistant option that works with a wide range of jack types and stores neatly in a compact bag, this kit delivers practical performance for seasonal campers and full-time nomads alike.