Pololu - Aluminum Standoff: 3/4 Length, 4-40 Thread, M-F (4-Pack)

These hexagonal male-female aluminum standoffs keep parts spaced 0.75" (19 mm) apart and are great for building a multi-level robot chassis. Both ends of these 3/16"-wide standoffs have 4-40 threads. The standoffs are sold in packs of 4.
These hexagonal male-female aluminum standoffs keep parts spaced 0.75 (19 mm) apart and are great for building a multi-level robot chassis. Both ends of these 3/16-wide standoffs have 4-40 threads. The standoffs are sold in packs of 4.

M3 x 4mm+6mm Hex Male-Female Standoffs,Male Thread Length 6mm,Brass,Pack 50-Piece: : Industrial & Scientific

Aluminum Standoff: 3/4 Length, 4-40 Thread, M-F (4-Pack) at MG Super Labs India

SO4-M4-20

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RS PRO, RS PRO Standoff, M4 x M4 Thread, 30mm Body, Nylon, Male/Female, 6mm Stud, 653-9419

Standoff Spacer Stud Fastener Pcb Spacer Standoff 3mm Hole - 4-40 Hex Male Female - Aliexpress

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Pololu - Claire's dead reckoning robot