Self-draining. Mansfield anti-siphon frostproof sillcocks assure protection against freezing and undesirable back-siphoning. Because they're frostproof, they can stop outside hydrants from freezing and bursting the pipes. Plus, the anti-siphon feature protects against water siphoning back to contaminate the potable water system. Also, unlike anti-siphon attachments, which must be manually drained to prevent freezing, the integral anti-siphon design is self-draining. 1/2" sweat inside, 1/2" IPS outside. No. 478-08: Size: 1/2 In. SWT x 1/2 In. IPS, Length: 8 In., Finish: Nickel Plated, Material: Brass, Pkg Qty: 1 No. 478-10: Size: 1/2 In. SWT x 1/2 In. IPS, Length: 10 In., Finish: Nickel Plated, Material: Brass, Pkg Qty: 1 No. 478-12: Size: 1/2 In. SWT x 1/2 In. IPS, Length: 12 In., Finish: Nickel Plated, Material: Brass, Pkg Qty: 1 No. 478-14: Size: 1/2 In. SWT x 1/2 In. IPS, Length: 14 In., Finish: Nickel Plated, Material: Brass, Pkg Qty: 1