It is made of No.45 steel, not stainless steel, but one type of Rui Fu, and
harder than ordinary iron! The rigid coupling is secured by four machine
screws! Each coupling comes with a locking nut, and each order includes one
wrench!!
The length of this coupling is: 22mm
The outer diameter has three options based on different hole diameters:
14mm, 16mm, and 18mm. Hole tolerance is±0.03mm (negligible).
Through-hole design; two hole diameters each occupy half of the
coupling length!
Widely applicable for motors, hardware, molds, and mechanical transmission
applications. 

Size Description:
The following 6 types have an outer diameter of 14 mm and a length of 22 mm:
4-4 indicates one end with 4mm hole diameter and the other end
with 4mm hole diameter; (side holes use M4 machine screws)
4-5 indicates one end with 4mm hole diameter and the
other end with 5mm; (side holes use M4machine screws)
4-6 indicates one end with 4mm hole diameter and the other end
with 6mm hole diameter; (side holes use M4machine screws)
5-5 indicates one end has a 5mm hole and the other end
has a 5mm hole; (side holes use M4machine screws)
5-6 indicates one end with 5mm hole diameter and the
other end with 6mm; (side holes use M4machine screws)
5-8 indicates one end with 5mm hole diameter and the other end
with 8mm hole diameter; (side holes use M4machine screws)
6-6 indicates one end has a 6mm hole and the other end
has a 6mm hole; (side holes use M4 machine screws)
6-8 indicates one end with 6mm hole diameter and the other end
with 8mm hole diameter; (side holes use M4 machine screws)  

8-8 indicates the aperture of 8mm at one end and 8mm at
the other end;(M4 screw for side holes)
The following three kinds of coupling, the outer diameter of 16 mm, the length of 22 mm:
6-10 indicates that the aperture of one end is 6 mm and the
aperture of the other end is10 mm; (M4 screw for side holes)
8-10 means that one side aperture 8mm, the other side
aperture 10mm; (M4 screw for side holes)
10-10 indicates one end with a hole diameter of 10 mm and the other end
with a hole diameter of 10 mm (side holes use M4machine screws)

Package Including:

 

The style you have chosen ×1pcs

 

 

Payment:

We accept Paypal only, It is fast, Easy and Safe.

Payment must be completed within 7 days.

PLEASE NOTE: S&H DOES NOT INCLUDE DUTIES, LOCATL TAXES OR ANY OTHER IMPORTATION FEES.

Please list your special requests (color, packages, etc.) in the PAYPAL NOTES SECTION when you make payment.

Shipping:

We Ship to Worldwide.

Orders processed within 24-48 hours of payment verification. it will take 15-25 days for delivery. but Customs will random inspection some parcel, so that's why some parcel need more than four weeks to arrive. Shipping time is only estimated and not guaranteed.

We only ship to confirmed PAYPAL addresses. Your PAYPAL address MUST MATCH your Shipping address.

Package to USA will Shipping by E-Package with Tracking Number(7-15 Days to Delivered). To other Countries will shipping by Post Air Mail without tracking number(ONLY when the order is over 20USD will supply Tracking Number Shipping Way!)(15-35 Days to Delivered)

Items are shipped via China Post Air Mail.

Guarantee:

Good Good quality. Buy with confidence!

If you are not satisfied when you receive your item, please return it within 7 days for a replacement or money back. Please contact me before you return it.

Not accept returning of electronic components.

Full refund after we receive our original item, Note: Return shipping is to be paid by the Buyer.

We maintain high standards of excellence and strive for 100% customer satisfaction! Feedback is very important to us. We request that you contact us immediately BEFORE you give us neutral or negative feedback, so that we can satisfactorily address your concerns.